U.S. patent application number 13/383893 was filed with the patent office on 2012-05-10 for sustained-release drug carrier composition.
This patent application is currently assigned to POLYPID LTD.. Invention is credited to Shlomo Barak, Noam Emanuel, Moshe Neuman.
Application Number | 20120114756 13/383893 |
Document ID | / |
Family ID | 43448999 |
Filed Date | 2012-05-10 |
United States Patent
Application |
20120114756 |
Kind Code |
A1 |
Emanuel; Noam ; et
al. |
May 10, 2012 |
SUSTAINED-RELEASE DRUG CARRIER COMPOSITION
Abstract
The present invention provides compositions for extended release
of one or more active ingredients, comprising a lipid-saturated
matrix formed from a non-biodegradable polymer or a
block-co-polymers comprising a non-biodegradable polymer and a
biodegradable polymer. The present invention also provides methods
of producing the matrix compositions and methods for using the
matrix compositions to provide controlled release of an active
ingredient in the body of a subject in need thereof.
Inventors: |
Emanuel; Noam; (Jerusalem,
IL) ; Neuman; Moshe; (Ramat Gan, IL) ; Barak;
Shlomo; (Tel Aviv, IL) |
Assignee: |
POLYPID LTD.
Kiryat Gat
IL
|
Family ID: |
43448999 |
Appl. No.: |
13/383893 |
Filed: |
July 14, 2010 |
PCT Filed: |
July 14, 2010 |
PCT NO: |
PCT/IL2010/000563 |
371 Date: |
January 13, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61225289 |
Jul 14, 2009 |
|
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Current U.S.
Class: |
424/486 ;
424/484; 514/169 |
Current CPC
Class: |
A61L 31/10 20130101;
A61P 35/00 20180101; A61K 9/1617 20130101; A61K 31/65 20130101;
A61P 31/10 20180101; A61L 24/0015 20130101; A61L 2300/416 20130101;
A61P 29/00 20180101; A61P 19/08 20180101; A61P 31/04 20180101; A61K
9/1647 20130101; A61L 2300/602 20130101; A61L 31/16 20130101; A61L
2300/22 20130101; A61L 27/54 20130101; A61L 27/34 20130101; A61K
9/1641 20130101; A61L 2300/406 20130101; A61P 1/02 20180101 |
Class at
Publication: |
424/486 ;
424/484; 514/169 |
International
Class: |
A61K 9/00 20060101
A61K009/00; A61P 19/08 20060101 A61P019/08; A61P 35/00 20060101
A61P035/00; A61P 29/00 20060101 A61P029/00; A61P 31/04 20060101
A61P031/04; A61K 31/56 20060101 A61K031/56; A61P 31/10 20060101
A61P031/10 |
Claims
1-45. (canceled)
46. A matrix composition comprising: a. a biocompatible
non-biodegradable polymer in association with a first lipid
comprising at least one sterol having a polar group; b. a second
lipid comprising at least one phospholipid having hydrocarbon
chains of at least 14 carbons; and c. at least one pharmaceutically
active agent; wherein the matrix composition is essentially free of
water and is adapted for providing sustained release of the
pharmaceutically active agent.
47. The matrix composition of claim 46, wherein said phospholipid
is a phosphatidylcholine having fatty acid moieties having at least
14 carbons.
48. The matrix composition of claim 46, further comprising a
biodegradable polymer.
49. The matrix composition of claim 48, wherein the
non-biodegradable polymer and the biodegradable polymer form a
block co-polymer.
50. The matrix composition of claim 46, wherein the
non-biodegradable polymer is selected from the group consisting of
polyethylene glycol (PEG), PEG acrylate, PEG methacrylate,
methylmethacrylate, ethylmethacrylate, butylmethacrylate,
2-ethylhexylmethacrylate, laurylmethacrylate, hydroxylethyl
methacrylate, 2-methacryloyloxyethylphosphorylcholine (MPC),
polystyrene, derivatized polystyrene, polylysine, poly
N-ethyl-4-vinyl-pyridinium bromide, poly-methylacrylate, silicone,
polyoxymethylene, polyurethane, polyamides, polypropylene,
polyvinyl chloride, polymethacrylic acid, and derivatives thereof
alone or as co-polymeric mixtures thereof.
51. The matrix composition of any one of claim 46, wherein the
non-biodegradable polymer is polyethylene glycol.
52. The matrix composition of claim 46, wherein the sterol is
cholesterol, and wherein the cholesterol is present in an amount of
5-50 mole percent of the total lipid content of said matrix
composition.
53. The matrix composition of claim 46 wherein the pharmaceutically
active agent is selected from the group consisting of an
antibiotic, an antifungal, a non-steroidal anti-inflammatory drug
(NSAID), a steroid, an anti-cancer agent, an osteogenic factor, a
bone resorption inhibitor and any combination thereof.
54. The matrix composition of claim 46, wherein the weight ratio of
total lipids to said biocompatible polymer is between 1.5:1 and 9:1
inclusive.
55. The matrix composition of claim 46, wherein said matrix
composition is homogeneous.
56. The matrix composition of claim 46, further comprising a
compound selected from the group consisting of: an additional
phospholipid selected from the group consisting of a
phosphatidylserine, a phosphatidylglycerol, and a
phosphatidylinositol; a free fatty acid having 14 or more carbon
atoms; a sphingolipid; a pegylated lipid and a tocopherol.
57. The matrix composition of claim 46, further comprising a
targeting moiety capable of interacting with a target molecule
selected from the group consisting of a collagen molecule, a fibrin
molecule and a heparin.
58. The matrix composition of claim 46, wherein at least 40% of
said pharmaceutically active agent is released from the composition
at zero-order kinetics.
59. An implant comprising the matrix composition of claim 46.
60. A pharmaceutical composition for sustained release of an active
agent comprising the matrix composition of claim 46.
61. A method of administering a pharmaceutically active agent to a
subject in need thereof, said method comprising administering to
the subject the matrix composition of claim 53, thereby
administering the pharmaceutically active agent to the subject.
62. A method of treating periodontitis in a subject in need
thereof, comprising administering to the subject the matrix
composition of claim 53, wherein the pharmaceutically active agent
is an osteogenic factor, a bone resorption inhibitor or a
combination thereof, thereby treating periodontitis in the
subject.
63. A method of stimulating bone augmentation in a subject in need
thereof, the method comprising the step of administering to said
subject the matrix composition of claim 53, thereby stimulating
bone augmentation in the subject.
64. A medical device comprising: a substrate and a biocompatible
coating deposited on at least a fraction of said substrate, wherein
the biocompatible coating comprises the matrix composition of claim
46.
65. The medical device of claim 64, wherein said biocompatible
coating includes multi-layers.
66. The medical device of claim 64, wherein said substrate is
selected from orthopedic nails, orthopedic screws, orthopedic
staples, orthopedic wires, orthopedic pins, metal or polymeric
implants, bone filler particles, collagen and non-collagen
membranes, suture materials, orthopedic cements and sponges.
67. A method of producing a matrix composition, the method
comprising the steps of: a. mixing into a first volatile organic
solvent: (i) a biocompatible non-biodegradable polymer and (ii) a
first lipid comprising at least one sterol having a polar group; b.
mixing into a second volatile organic solvent: (i) at least one
pharmaceutically active agent; (ii) a second lipid selected from
phospholipids having hydrocarbon chain of at least 14 carbons; and
c. mixing the products resulting from steps (a) and (b), to produce
a homogeneous mixture; and d. evaporating the volatile organic
solvents; wherein each of the steps (a)-(d) is essentially free of
an aqueous solution, thereby producing a homogeneous matrix
composition essentially free of water.
68. The method of claim 67, wherein step (a) further comprising
mixing into the first volatile organic solvent a biodegradable
polymer.
69. The method of claim 68 wherein the non-biodegradable polymer
and the biodegradable polymer form a block co-polymer.
70. The method of claim 67, wherein the non-biodegradable polymer
is selected from the group consisting of polyethylene glycol (PEG),
PEG acrylate, PEG methacrylate, methylmethacrylate,
ethylmethacrylate, butylmethacrylate, 2-ethyl hexyl methacrylate,
laurylmethacrylate, hydroxylethyl methacrylate,
2-methacryloyloxyethylphosphorylcholine (MPC), polystyrene,
derivatized polystyrene, polylysine, poly
N-ethyl-4-vinyl-pyridinium bromide, poly-methylacrylate, silicone,
polyoxymethylene, polyurethane, polyamides, polypropylene,
polyvinyl chloride, polymethacrylic acid, and derivatives thereof
alone or as co-polymeric mixtures thereof.
71. The method of claim 70, wherein the non-biodegradable polymer
is polyethylene glycol (PEG).
Description
FIELD OF THE INVENTION
[0001] The present invention provides compositions for extended
release of an active ingredient, comprising a lipid-based matrix
with a non-biodegradable polymer. The present invention also
provides methods of producing the matrix compositions and methods
for using the matrix compositions to provide controlled release of
an active ingredient in the body of a subject in need thereof.
BACKGROUND OF THE INVENTION
[0002] Lipid based drug delivery systems are well known in the art
of pharmaceutical science. Typically they are used to formulate
drugs having poor bioavailability or high toxicity or both. Among
the prevalent dosage forms that have gained acceptance are many
different types of liposomes, including small unilamellar vesicles,
multilamellar vesicles and many other types of liposomes; different
types of emulsions, including water in oil emulsions, oil in water
emulsions, water-in-oil-in-water double emulsions, submicron
emulsions, microemulsions; micelles and many other hydrophobic drug
carriers. These types of lipid based delivery systems can be highly
specialized to permit targeted drug delivery or decreased toxicity
or increased metabolic stability and the like. Extended release in
the range of days, weeks and more are not profiles commonly
associated with lipid based drug delivery systems in vivo.
[0003] Ideally sustained release drug delivery systems should
exhibit kinetic and other characteristics readily controlled by the
types and ratios of the specific excipients used. Advantageously
the sustained release drug delivery systems should provide
solutions for hydrophilic, amphipathic as well as hydrophobic
drugs.
[0004] Periodontitis
[0005] The use of systemic doxycycline and NSAIDs in combination
therapy has been shown to suppress tissue damage in the gingiva of
chronic periodontitis patients. Tissue damage is caused by the
action of pathogenic bacteria in combination with host matrix
metalloproteinase (MMP) activity. Antibiotic treatment in
combination with anti-inflammatory medication suppresses these two
pathways. An increase in efficacy and reduction of side effects of
treatment would be achieved by a means of releasing these
medications locally in a controlled fashion.
[0006] Bone Augmentation
[0007] Bone diseases requiring bone augmentation include benign and
malignant bone tumors, cancers situated in bones, infectious bone
diseases, and other bone diseases of etiology related to
endocrinology, autoimmunity, poor nutrition, genetic factors, and
an imbalance between bone growth and resorption. Examples are
diseases such as osteosarcoma/malignant fibrous histiocytoma of
bone (PDQ), osteosarcoma, chondrosarcoma, Ewing's sarcoma,
malignant fibrous histiocytoma, fibrosarcoma and malignant fibrous
histiocytoma, giant cell tumor of bone, chordoma, lymphoma,
multiple myeloma, osteoarthritis, Paget's disease of bone,
arthritis, degenerative changes, osteoporosis, osteogenesis
imperfecta, bone spurs, renal osteodystrophy, hyperparathyroidism,
osteomyelitis, enchondroma, osteochondroma, osteopetrosis, bone and
joint problems associated with diabetes.
[0008] Immediate and delayed infection is a major complication in
the field of orthopedics. Reducing the complications after
orthopedic treatment will induce the efficiency and success of the
orthopedic treatment and in some cases it will reduce the
mortality. There is also a need to allow treatment in infected
sites and to induce the efficacy of the treatment in the infected
sites.
[0009] Another important aspect in the field of orthopedics or
orthopedic surgery is the need to accelerate soft and hard tissue
recovery in reparative and regenerative procedures.
[0010] Bone augmentation further comprises a variety of procedures
that are used to "build" bone so that implants can be placed. These
procedures typically involve grafting bone or bonelike materials to
the treated area (e.g. lost bone as a result of bone tumor or
cancer metastasis removal) and waiting for the grafted material to
fuse with the existing bone over several months. Typically, bone
removal surgery for the removal of tumor is followed by
chemotherapy or radiology treatment. One of the drawbacks of
systemic chemotherapy is its limited ability to completely
eradicate potential left-over tumor cells due to the limited blood
supply in the grafted area. Furthermore, radio-therapy is limited
due to the slow recovery of the injured bone. Therefore, slow and
long term release of anti-cancer agents, directly in the location
needed would be highly beneficial.
[0011] Liposomes and Biodegradable Polymers in Drug Delivery
[0012] To date the use of lipids in conjunction with biopolymers
has been contemplated but these have not yet been introduced
successfully into clinical practice.
[0013] U.S. Pat. No. 3,773,919 to Boswell et al describes the use
of polymers derived from alpha-hydroxycarboxylic acids including
lactic acid, glycolic acid and co-polymers thereof and their use in
sustained release formulations.
[0014] Liposomes are described in U.S. Pat. No. 4,522,803 to Lenk
et al. Liposomes typically exhibit adequate drug delivery
drug-holding capacity but relatively limited in vivo half-lives.
Many different types of liposomes have been developed for
particular applications. Examples can be found in U.S. Pat. Nos.
5,043,166; 5,316,771; 5,919,480; 6,156,337; 6,162, 462; 6,787,132;
7,160,554, among others.
[0015] U.S. Pat. Nos. 6,333,021 and 6,403,057 to Schneider et al
disclose microcapsules having a biodegradable membrane
encapsulating a gas core.
[0016] U.S. Pat. Nos. 6,277,413 and 6,793,938 to Sankaram disclose
biodegradable lipid/polymer-containing compositions prepared by
utilizing aqueous solutions, precluding formation of a
water-resistant, lipid-saturated matrix.
[0017] U.S. Pat. No. 4,882,167 to Jang discloses a controlled
release matrix for tablets or implants of biologically active
agents produced by dry direct compression of a hydrophobic
carbohydrate polymer, e.g. ethyl cellulose; and a
difficult-to-digest soluble component, i.e. a wax, e.g. carnauba
wax, a fatty acid material, or a neutral lipid.
[0018] US Patent Application 2006/0189911 to Fukuhira et al
discloses an anti-adhesion membrane of a honeycomb film made of
polylactic acid as a biodegradable polymer and a phospholipid.
[0019] US Patent Application 2004/0247624 discloses methods for the
preparation of a pharmaceutical composition comprising an organic
solvent, a drug and a stabilizing agent selected from a polymer, a
lipid, a polymer-lipid conjugate or a combination thereof.
[0020] US Patent Application 2006/0073203 to Ljusberg-Wahren et al
discloses an orally administrable composition comprising a dry
mixture of polymer, lipid and bioactive agent, intended upon
contact with water or gastrointestinal fluids to form particles
comprising the lipid, the bioactive agent, and optionally also
water. The polymers utilized, disintegrate in the digestive tract
during the digestive process; e.g. a time period of less than one
day.
[0021] International Patent Application Publication WO/2010/007623
to the inventors of the present invention provides compositions for
extended release of an active ingredient, comprising a
lipid-saturated matrix formed from a polyester based biodegradable
polymer.
[0022] Despite the advances recently made in the art, there is an
immediate need for improved compositions adapted to achieve
sustained release or programmed release or controlled release from
a lipid-saturated polymeric matrix for periodontal or orthopedic
uses.
SUMMARY OF THE INVENTION
[0023] Embodiments of the present invention provide compositions
for extended release of an active ingredient, comprising a
lipid-based matrix comprising a non-biodegradable polymer. Other
embodiments of the present invention provide methods of producing
the matrix compositions and methods for using the matrix
compositions to provide controlled release of an active ingredient
in the body of a subject in need thereof.
[0024] In one aspect, the present invention provides a matrix
composition comprising: (a) a pharmaceutically acceptable,
biocompatible non-biodegradable polymer in association with a first
lipid having a polar group; (b) a second lipid selected from
phospholipids having fatty acid moieties of at least 14 carbons;
and (c) a pharmaceutical active agent, where the matrix composition
is adapted for providing sustained release of the pharmaceutical
agent. According to some embodiments, the first lipid having a
polar group comprises at least one sterol. According to some
embodiments, the first lipid having a polar group is other than a
phospholipid. According to some embodiments, the first lipid
comprises a mixture of lipids. According to some embodiments, the
first lipid comprises a mixture of lipids wherein at least one of
the lipids is a sterol. According to some embodiments, the
non-biodegradable polymer is not bonded to the first lipid having a
polar group. According to some embodiments, the second lipid
comprises a mixture of lipids, wherein at least one is a
phospholipid having fatty acid moieties of at least 14 carbons
According to some embodiments, the non-biodegradable polymer is not
bonded to the second lipid. According to some embodiments, the
non-biodegradable polymer is not bonded to the phospholipids.
According to some preferable embodiments, the first lipid and the
second lipid are distinct category of lipids. In specific
embodiments, the polymer and the phospholipids form a matrix
composition that is substantially free of water.
[0025] According to some embodiments, the non-biodegradable polymer
may comprise polyethylene glycol, polyethylene glycol (PEG)
acrylate, polymethacrylates (e.g. PEG methacrylate,
polymethylmethacrylate, polyethylmethacrylate,
polybutylmethacrylate, poly-2-ethylhexylmethacrylate,
polylaurylmethacrylate, polyhydroxylethyl methacrylate),
poly-methylacrylate, 2-methacryloyloxyethylphosphorylcholine (MPC),
polystyrene, derivatized polystyrene, polylysine, poly
N-ethyl-4-vinyl-pyridinium bromide, silicone, ethylene-vinyl
acetate copolymers, polyethylenes, polypropylenes,
polytetrafluoroethylenes, polyurethanes, polyacrylates, polyvinyl
acetate, ethylene vinyl acetate, polyethylene, polyvinyl chloride,
polyvinyl fluoride, copolymers of polymers of ethylene-vinyl
acetates and acyl substituted cellulose acetates, poly(vinyl
imidazole), chlorosulphonate polyolefins, polyethylene oxide,
polyoxymethylene (Delrin.RTM.), polyurethane, polyamides,
polypropylene, polyvinyl chloride, polymethacrylic acid, and
derivatives thereof alone and mixtures thereof.
[0026] According to particular embodiment, the non-biodegradable
polymer comprises polyethylene glycol having a molecular weight
from about 1000 to about 20000; alternatively, between 2000 to
about 10000. According to an exemplary embodiment, the polyethylene
glycol has a molecular weight between about 4000 to about 8000.
[0027] In another aspect, the present invention provides a matrix
composition comprising: (a) a pharmaceutically acceptable,
biocompatible biodegradable polymer other than a polyester in
association with a first lipid having a polar group; (b) a second
lipid selected from phospholipids having fatty acid moieties of at
least 14 carbons; and (c) a pharmaceutical active agent, where the
matrix composition is adapted for providing sustained release of
the pharmaceutical agent. In specific embodiments, the polymer and
the phospholipids form a matrix composition that is substantially
free of water.
[0028] According to some embodiment, the biodegradable polymer is
selected from the group consisting of poly(caprolactone),
polycarbonates, polyesteramides, polyanhydrides, poly(amino acid)s,
polycyanoacrylates, polyamides, polyacetals, poly(ether ester)s,
poly(dioxanone)s, poly(alkylene alkylate)s, biodegradable
polyurethanes, blends and copolymers thereof.
[0029] According to some embodiments, the polymer may include any
combination of a non-biodegradable polymer and a biodegradable
polymer. According to some particular embodiments, the polymer may
include any combination of a non-biodegradable polymer and a
biodegradable polymer other than a polyester. According to some
embodiments, the polymer may include more than one type of a
non-biodegradable polymer, more than one type of a biodegradable
polymer or a combination thereof.
[0030] According to some embodiments, the matrix composition
further comprises a biodegradable polymer, wherein the
non-biodegradable polymer and the biodegradable polymer form a
block co-polymer. According to some embodiments, the block
co-polymer is a linear co-polymer ((AB)n, (ABA)n or (ABABA)n
wherein n.gtoreq.1). According to some other embodiments, the block
co-polymer is a branched co-polymer (multiple A's depending from
one B). In these formulae, A is a non-biodegradable polymer and B
is a biodegradable polymer; alternatively, A is a non-biodegradable
polymer and B is a biodegradable polymer other than a polyester.
According to some embodiments, A is a non-biodegradable polymer
having a molecular weight lower than 5000 dalton; alternatively,
lower than 4000 dalton; alternatively, lower than 3000 dalton;
alternatively, lower than 2000 dalton. Non-limiting examples of
suitable block co-polymers include PEG-PLA-PEG and PEG-PLGA-PEG.
According to some embodiments, the polymer may include any
combination of a non-biodegradable polymer, a biodegradable polymer
and a block co-polymer as defined above. According to some
embodiments, the block co-polymer comprises more than one type of
non-biodegradable polymer, more than one type of biodegradable
polymer or a combination thereof. Each possibility represents a
separate embodiment of the present invention.
[0031] According to some embodiments, the polymer comprises
non-biodegradable polymer chains having a molecular weight lower
than 5000 dalton, linked to each other by a biodegradable linker.
Non limiting examples of biodegradable linkers include disulfide
bonds and ester bonds.
[0032] According to some embodiments the first lipid having a polar
group is selected from a sterol, a tocopherol and a
phosphatidylethanolamine. According to some embodiments, the first
lipid having a polar group is selected from a sterol. According to
particular embodiments the first lipid is mixed with the
biocompatible polymer to form a non-covalent association. According
to some exemplary embodiments, the first lipid having a polar group
is cholesterol.
[0033] According to some embodiments the second lipid comprises a
phosphatidylcholine. According to some embodiments the second lipid
comprises a mixture of phosphatidylcholines. According to some
embodiments the second lipid comprises a mixture of a
phosphatidylcholine and a phosphatidylethanolamine, or any other
types of phospholipids.
[0034] Any type of drug molecule may be incorporated into the
matrix compositions for sustained and/or controlled release and/or
extended release. According to particular embodiments the
pharmaceutically active agent is selected from the group consisting
of an antibiotic, an antifungal, an NSAID, a steroid, an
anti-cancer agent, an osteogenic factor, a bone resorption
inhibitor and any combination thereof. According to alternative
embodiments the pharmaceutical active agent is selected from a
hydrophobic agent, an amphipathic agent or a water soluble agent.
Each possibility represents a separate embodiment of the present
invention.
[0035] In another embodiment, the phospholipid is a
phosphatidylcholine having fatty acid moieties of at least 14
carbons. In another embodiment, the composition further comprises a
phosphatidylethanolamine having fatty acid moieties of at least 14
carbons. In another embodiment, the matrix composition is
homogeneous. In another embodiment, the matrix composition is in
the form of a lipid-based matrix whose shape and boundaries are
determined by the polymer. In another embodiment, the matrix
composition is in the form of an implant.
[0036] In some embodiments, the pharmaceutical active agent is an
antibiotic incorporated into the matrix composition. In some
embodiments, the antibiotic has low water solubility. In another
embodiment, the antibiotic is a hydrophobic antibiotic. In another
embodiment, the antibiotic is an amphipathic antibiotic. In another
embodiment, the composition further comprises a non-steroidal
anti-inflammatory drug (NSAID). In another embodiment, the NSAID as
well is incorporated into the matrix composition. In another
embodiment, the NSAID has low water solubility. In another
embodiment the matrix composition may comprise a combination of two
or more active agents. In another embodiment, the matrix
composition may comprise a combination of an antibiotic and a
NSAID. Each possibility represents a separate embodiment of the
present invention.
[0037] In a particular embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having fatty acid moieties
of at least 14 carbons; (d) a phosphatidylcholine having fatty acid
moieties of at least 14 carbons; and (e) an antibiotic or
antifungal agent. In another embodiment, the matrix composition
comprises at least 50% lipid by weight. In another embodiment, the
matrix composition is homogeneous. In another embodiment, the
matrix composition is in the form of a lipid-based matrix whose
shape and boundaries are determined by the polymer. In another
embodiment, the matrix composition is in the form of an
implant.
[0038] According to some exemplary embodiments, the present
invention provides a matrix composition comprising: (a)
polyethylene glycol; (b) a sterol; (c) a phosphatidylcholine having
fatty acid moieties of at least 14 carbons; and (d) an antibiotic
or antifungal agent. In another embodiment, the matrix composition
comprises at least 30% lipid (sterol and phospholipids) by weight.
In another exemplary embodiment, the sterol is cholesterol. In
another embodiment, the matrix composition is homogeneous. In
another embodiment, the matrix composition is in the form of a
lipid-based matrix whose shape and boundaries are determined by the
polymer. In another embodiment, the shape and boundaries of the
matrix composition are determined by the polymer in compositions
comprising at least 50% polymer by weight. In another embodiment,
the matrix composition is in the form of an implant.
[0039] According to alternative embodiments the antibiotic or
antifungal agent is selected from a hydrophobic agent, an
amphipathic agent or a water soluble agent. Each possibility
represents a separate embodiment of the present invention.
[0040] In another embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having fatty acid moieties
of at least 14 carbons; (d) a phosphatidylcholine having fatty acid
moieties of at least 14 carbons; and (e) a non-steroidal
anti-inflammatory drug (NSAID). In another embodiment, the matrix
composition comprises at least 30% lipid. In another embodiment,
the NSAID has low water solubility. In another embodiment, the
NSAID is a hydrophobic NSAID. In another embodiment, the NSAID is
an amphipathic NSAID. In another embodiment, the matrix composition
is in the form of a lipid-based matrix whose shape and boundaries
are determined by the polymer. In another embodiment, the shape and
boundaries of the matrix composition are determined by the polymer
in compositions comprising at least 50% polymer by weight.
[0041] In another embodiment, the matrix composition is in the form
of an implant. In another embodiment, the matrix composition is
homogeneous. Each possibility represents a separate embodiment of
the present invention.
[0042] In another embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having fatty acid moieties
of at least 14 carbons; (d) a phosphatidylcholine having fatty acid
moieties of at least 14 carbons; and (e) an osteogenic factor or a
bone resorption inhibitor. In another embodiment, the matrix
composition comprises at least 30% lipid. In another embodiment,
the bone resorption inhibitor has low water solubility. In another
embodiment, the bone resorption inhibitor is a hydrophobic bone
resorption inhibitor. In another embodiment, the bone resorption
inhibitor is an amphipathic bone resorption inhibitor. In another
embodiment, the composition further comprises an NSAID. In another
embodiment, the NSAID as well is incorporated into the matrix
composition. In another embodiment, the matrix composition is in
the form of a lipid-based matrix whose shape and boundaries are
determined by the polymer. In another embodiment, the shape and
boundaries of the matrix composition are determined by the polymer
in compositions comprising at least 50% polymer by weight. In
another embodiment, the matrix composition is in the form of an
implant. In another embodiment, the matrix composition is
homogeneous. Each possibility represents a separate embodiment of
the present invention.
[0043] In another embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having saturated fatty acid
moieties of at least 14 carbons; (d) a phosphatidylcholine having
saturated fatty acid moieties of at least 14 carbons; (e) an active
agent; and (f) a targeting moiety capable of interacting with a
surface molecule of a target cell. In another embodiment, the
active agent is selected from the group consisting of an NSAID, an
antibiotic, an antifungal agent, a steroid, an anti-cancer agent,
an osteogenic factor and a bone resorption inhibitor. In another
embodiment, the polymer and the phospholipid form a matrix
composition that is substantially free of water. In another
embodiment, the matrix composition is capable of being degraded in
vivo to vesicles into which some or all the mass of the released
active agent is integrated. In another embodiment, the matrix
composition is capable of being degraded in vivo to form vesicles
into which the active agent and the targeting moiety are
integrated. Each possibility represents a separate embodiment of
the present invention.
[0044] In another embodiment, the present invention provides a
pharmaceutical composition comprising a matrix composition of the
present invention and a pharmaceutically acceptable excipient. In
another embodiment, the matrix composition is in the form of
microspheres. In another embodiment, the present invention provides
a pharmaceutical composition comprising microspheres of the present
invention and a pharmaceutically acceptable excipient. In another
embodiment, the pharmaceutical composition is in a parenterally
injectable form. In another embodiment, the pharmaceutical
composition is in an infusible form. In another embodiment, the
excipient is compatible for injection. In another embodiment, the
excipient is compatible for infusion. Each possibility represents a
separate embodiment of the present invention.
[0045] In another embodiment, a matrix composition of the present
invention is in the form of an implant, following evaporation of
the organic solvents. In another embodiment, the implant is
homogeneous. Each possibility represents a separate embodiment of
the present invention.
[0046] In some embodiments, the polymer of the present invention is
associated with the sterol via non-covalent bonds. In some
embodiments, the polymer of the present invention is associated
with the sterol via hydrogen bonds.
[0047] In another embodiment, the process of creating an implant
from a composition of the present invention comprises the steps of
(a) creating a matrix composition according to a method of the
present invention in the form of a bulk material; and (b)
transferring the bulk material into a mold or solid receptacle of a
desired shape.
[0048] Also provided herein are methods for making the compositions
of the invention and methods of use thereof.
[0049] According to another aspect a matrix composition for
sustained release of a pharmaceutical agent is generated by a
process comprising: providing a first solution or dispersion of a
volatile organic solvent comprising a biocompatible polymer
selected from the group consisting of a non-biodegradable polymer,
a biodegradable polymer other than polyester or a combination
thereof, and a first lipid having a polar group; providing a second
solution or dispersion comprising a second volatile organic solvent
and a second lipid, the second lipid comprising at least one
phospholipid, and a pharmaceutical active agent; mixing the first
and second solutions to form a homogeneous mixture; evaporating the
volatile solvents to produce a homogeneous polymer phospholipid
matrix comprising a pharmaceutical active agent. The selection of
the specific solvents is made according to the specific drug and
other substances used in the particular formulation intended to
entrap a specific active and to release it in a specific
pre-planned rate and duration. The evaporation is conducted at
controlled temperature determined according to the properties of
the solution obtained. According to some embodiments, the volatile
organic solvents used in methods of the invention had a freezing
temperature lower than 0.degree. C.; alternatively, lower than
10.degree. C.; alternatively, lower than 20.degree. C.
[0050] According to the present disclosure the use of different
types of volatile organic solutions, and the absence of water
throughout the process, enable the formation of homogeneous
water-resistant, lipid based matrix compositions. According to
various embodiments the first and second solvents can be the same
or different. According to some embodiments one solvent can be
non-polar and the other preferably water-miscible.
[0051] In another embodiment, the matrix composition of methods and
compositions of the present invention is substantially free of
water. "Substantially free of water" refers, in another embodiment,
to a composition containing less than 1% water by weight. In
another embodiment, the term refers to a composition containing
less than 0.8% water by weight. In another embodiment, the term
refers to a composition containing less than 0.6% water by weight.
In another embodiment, the term refers to a composition containing
less than 0.4% water by weight. In another embodiment, the term
refers to a composition containing less than 0.2% water by weight.
In another embodiment, the term refers to the absence of amounts of
water that affect the water-resistant properties of the
composition. In another embodiment, the term refers to a
composition manufactured without the use of any aqueous solvents.
In another embodiment, producing the composition using a process
substantially free of water, as described herein, enables lipid
saturation. Lipid saturation confers upon the matrix composition
ability to resist bulk degradation in vivo; thus, the matrix
composition exhibits the ability to mediate extended release on a
scale of several days, weeks or months.
[0052] In another embodiment, the matrix composition is essentially
free of water. "Essentially free" refers to a composition
comprising less than 0.1% water by weight. In another embodiment,
the term refers to a composition comprising less than 0.08% water
by weight. In another embodiment, the term refers to a composition
comprising less than 0.06% water by weight. In another embodiment,
the term refers to a composition comprising less than 0.04% water
by weight. In another embodiment, the term refers to a composition
comprising less than 0.02% water by weight. In another embodiment,
the term refers to a composition comprising less than 0.01% water
by weight. Each possibility represents a separate embodiment of the
present invention.
[0053] In another embodiment, the matrix composition is free of
water. In another embodiment, the term refers to a composition not
containing detectable amounts of water. Each possibility represents
a separate embodiment of the present invention.
[0054] In another embodiment, the present invention provides a
method of producing a matrix composition, the method comprising the
steps of (a) combining with a non-polar, volatile organic solvent:
(i) a non-biodegradable polymer, a biodegradable polymer other than
polyester or a combination thereof and (ii) a sterol; (b) combining
with a water-miscible, volatile organic solvent: (i) an active
agent selected from the group consisting of a non-steroidal
anti-inflammatory drug (NSAID), an antibiotic, an antifungal a
steroid, an anti-cancer agent, and osteogenic factor, a bone
resorption inhibitor and any combination thereof; (ii) a
phosphatidylethanolamine; and (iii) a phosphatidylcholine; and (c)
mixing and homogenizing the products resulting from steps (a) and
(b). In another embodiment, the phosphatidylethanolamine is
included in the non-polar, volatile organic solvent instead of the
water-miscible, volatile organic solvent. In another embodiment,
the non-biodegradable polymer is selected from the group consisting
of polyethylene glycol, polyethylene glycol (PEG) acrylate,
polymethacrylates (e.g. PEG methacrylate, polymethylmethacrylate,
polyethylmethacrylate, polybutylmethacrylate,
poly-2-ethylhexylmethacrylate, polylaurylmethacrylate,
polyhydroxylethyl methacrylate), poly-methylacrylate,
2-methacryloyloxyethylphosphorylcholine (MPC), polystyrene,
derivatized polystyrene, polylysine, poly
N-ethyl-4-vinyl-pyridinium bromide, silicone, ethylene-vinyl
acetate copolymers, polyethylenes, polypropylenes,
polytetrafluoroethylenes, polyurethanes, polyacrylates, polyvinyl
acetate, ethylene vinyl acetate, polyethylene, polyvinyl chloride,
polyvinyl fluoride, copolymers of polymers of ethylene-vinyl
acetates and acyl substituted cellulose acetates, poly(vinyl
imidazole), chlorosulphonate polyolefins, polyethylene oxide, and
mixtures thereof. In another embodiment, the non-biodegradable
polymer is any other suitable non-biodegradable polymer known in
the art. In another embodiment, the mixture containing the
non-polar, organic solvent is homogenized prior to mixing it with
the mixture organic solvent. In another embodiment, the mixture
containing the water-miscible, organic solvent is homogenized prior
to mixing it with the mixture containing the non-polar, organic
solvent. In another embodiment, the polymer in the mixture of step
(a) is lipid saturated. In another embodiment, the matrix
composition is lipid saturated. Each possibility represents a
separate embodiment of the present invention.
[0055] In another embodiment, the matrix composition of the present
invention can be used for coating fully or partially the surface of
different substrates. In another embodiment substrates to be coated
include at least one material selected from the group consisting of
carbon fibers, stainless steel, cobalt-chromium, titanium alloy,
tantalum, ceramic and collagen or gelatin. In another embodiment
substrates may include any medical devices such as orthopedic
nails, orthopedic screws, orthopedic staples, orthopedic wires and
orthopedic pins used in orthopedic surgery, metal or polymeric
implants used in both orthopedic and periodontal surgery, bone
filler particles and absorbable gelatin sponge. Bone filler
particles can be any one of allogeneic (i.e., from human sources),
xenogeneic (i.e., from animal sources) and artificial bone
particles. In another embodiment a treatment using the coated
substrates and administration of the coated substrates will follow
procedures known in the art for treatment and administration of
similar uncoated substrates. In another embodiment bone filler
particles coated with the matrix of the present invention are
administered substantially as a single ingredient (not administered
as part of a mixture with other ingredients). Alternatively, the
coated bone filler particles are mixed with any other commercially
available bone filler particles or autologous bone before
administration. In another embodiment, the mixture of bone filler
particles comprises at least one of: non-coated particles,
particles coated with matrix compositions incorporating a
pharmaceutically active agent, particles coated with matrix
compositions incorporating a plurality of pharmaceutically active
agents or a combination thereof. In another embodiment the amounts,
ratios and types of ingredients forming the matrix composition of
the present invention are varied so to adjust the polymer-lipid
basis to the biophysical/biochemical properties of the
pharmaceutically active agent, the therapeutically effective dose
of the pharmaceutically active agent and to the desired sustained
release time period (typically in the range of days to months). In
another embodiment bone filler particles coated with matrix
composition comprising an active agent are mixed with bone filler
particles coated with matrix composition comprising a different
active agent before administration. It is to be emphasized that
within the scope of the present invention are bone particles coated
with different matrix compositions comprising different active
agents, compositions comprising different lipid/polymer ratio,
compositions comprising different lipid content or any combination
thereof. Such mixtures may be used for combination treatment in
which the release rate of each of the active agents is separately
controlled.
[0056] It is to be emphasized that the sustained release period
using the compositions of the present invention can be programmed
taking into account two major factors: (i) the weight ratio between
the polymer and the lipid content, specifically the phospholipid
having fatty acid moieties of at least 14 carbons, and (ii) the
biochemical and/or biophysical properties of the polymer and the
lipid. Specifically, the fluidity of the lipid should be
considered. For example, a phosphatidylcholine (14:0) is more fluid
(less rigid and less ordered) at body temperature than a
phosphatidylcholine (18:0). Thus, for example, the release rate of
a drug incorporated in a matrix composition comprising PEG 8000 and
phosphatidylcholine (18:0) will be slower than that of a drug
incorporated in a matrix composed of PEG 8000 and
phosphatidylcholine (14:0).
[0057] When the polymer used in the matrix composition comprises
polymer units having a molecular weight of up to 5000 dalton linked
by a biodegradable linker, the nature of the biodegradable linker
may influence the release period of the active agent
entrapped/encapsulated in the composition. Alternatively, when the
polymer comprises a block co-polymer according to embodiments of
the invention, the nature of the biodegradable polymer units of the
block co-polymer may influence the release period of the active
agent entrapped/encapsulated in the composition. Another aspect
that will determine the release rate is the physical
characteristics of the entrapped or impregnated drug. In addition,
the release rate of drugs can further be controlled by the addition
of other lipids into the formulation of the second solution. This
can includes fatty acids of different length such as lauric acid
(12:0), membrane active sterols (such as cholesterol) or other
phospholipids such as phosphatidylethanolamine. According to
various embodiments the active agent is released from the
composition over a desired period ranging between several days to
several months.
[0058] These and other features and advantages of the present
invention will become more readily understood and appreciated from
the detailed description of the invention that follows.
BRIEF DESCRIPTION OF THE FIGURES
[0059] FIG. 1: A) TLC runs of extracted cholesterol (CH) from
different matrix compositions; 1: PEG+CH+doxycycline hyclate
(Doxy-H); 2: PEG+CH+Doxy-H+DMPC; 3: PEG+CH+Doxy-H+DSPC; 4: CH only
(control); B) TLC runs of extracted phospholipids (DPPC) from
PEG+CH+Doxy-H+DPPC matrix composition.
[0060] FIG. 2: The release profile of Doxy-H entrapped/encapsulated
within TCP-matrix compositions after spin-down. A) Amount of Doxy-H
released versus time from matrix compositions comprising PEG, CH,
Doxy-H and DSPC (18:0) (large squares) and PEG, CH, Doxy-H and DMPC
(14:0) (small squares); B) The percentage of Doxy-H released (of
the total amount of Doxy-H encapsulated within the matrix
composition comprising PEG, CH, Doxy-H and DPPC (16:0)) versus
time.
[0061] FIG. 3: Particles released after hydration of two different
matrix compositions: A) matrix composition comprising PEG and
Doxy-H; B) matrix composition comprising PEG, CH, Doxy-H and
phospholipids.
[0062] FIG. 4: Differential scanning calorimetry (DSC) scans of
PEG, cholesterol and a combination of PEG and cholesterol at
different ratios.
[0063] FIG. 5: Polymer: drug interaction analysis; A) DSC scans of
PEG, Doxy-H, PEG-Doxy, PEG-CH-Doxy-H and PEG-CH-Doxy-H-DPPC. B)
Zoom into the Doxy-H endothermic peak range (190-210.degree.
C.)
[0064] FIG. 6: Polymer: phospholipid interaction analysis; A) Full
range of DSC scans of PEG, DPPC, PEG-DPPC and PEG-CH-DPPC. B) Zoom
into the DPPC endothermic peak range (90-110.degree. C.).
DETAILED DESCRIPTION OF THE INVENTION
[0065] Embodiments of the present invention provides compositions
for extended release of an active ingredient, comprising a
lipid-based matrix comprising a non-biodegradable polymer, a
biodegradable polymer which is other than polyester, a
block-co-polymers of biodegradable and non biodegradable polymers
or a combination thereof. The present invention also provides
methods of producing the matrix compositions and methods for using
the matrix compositions to provide controlled release of an active
ingredient in the body of a subject in need thereof.
[0066] The matrix composition according to the embodiments of the
present invention display many advantages over known in the art
matrix composition comprising biodegradable polymers. Matrix
composition comprising non-biodegradable polymers are inert. As
such they are less prone to interference with the surrounding
environment and influence tissue functions. Typically,
non-biodegradable polymers are hypoallergenic and do not interfere
with the activity of the immune system. Furthermore, the sub
structure of non-biodegradable polymers is stable and cannot be
further metabolized by bacteria and/or fungi in contrast to the
degradation products of biodegradable polymers.
[0067] Another advantage of using non-biodegradable polymers in the
matrix compositions of the invention relates to the drug
entrapped/encapsulates within the matrix. When using biodegradable
polymers, the physical environment within the matrix composition
and in close proximity to the matrix composition may alter due to
the degradation of the polymers; for example: PLGA, PLA and PLG may
elevate the local acidity due to the release of lactic acid and/or
glycolic acid monomers. This may be crucial when the entrapped or
encapsulated drug is pH sensitive (e.g. polypeptides and protein
based drugs).
[0068] Matrix composition comprising non-biodegradable polymers,
specifically non-biodegradable polymers having a molecular weight
above 5000 dalton, may serve as a permanent/long term physical
backbone support to the lipidic component, supporting the overall
structure of an implant or another medical device coated with the
matrix composition during as well as after the release of the drug
and the lipids.
[0069] Other advantages of using matrix formulations comprising
non-biodegradable compositions include: a) Cost: some of the
non-biodegradable polymers such as PEG, are relatively cheap
compared to polyesters; b) Elimination: low molecular
non-biodegradable polymers such as PEG (MW.ltoreq.5 KD) are easily
eliminated from the body through the urine; c) Easy to work with:
Non-biodegradable polymers are less sensitive to the
physical/chemical conditions (e.g. temp, pH) required during
preparation.
[0070] The term "controlled release" refers to control of the rate
and/or quantity of pharmaceutically active agent(s) delivered by
the matrix compositions of the invention. The controlled release
can be continuous or discontinuous, and/or linear or
non-linear.
[0071] The term "sustained release" means that the active agent or
drug is released at a rate that is significantly slower than the
release expected due to diffusion under the same physical and
chemical conditions. As used herein sustained release means that
the release profile will provide a local therapeutically effective
concentration over a period of days or weeks or months. The
systemic concentrations may be significantly lower than the local
concentrations of release from the matrix to the desired site of
action, thereby achieving decreased toxicity as well as prolonged
therapeutic effectiveness.
[0072] In certain embodiments, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
phosphoglyceride having hydrocarbon moieties of at least 14
carbons; and (c) a pharmaceutical active agent. According to some
embodiments the pharmaceutical agent is selected from the group
consisting of an antibiotic, an antifungal, an NSAID, a steroid, an
anticancer agent, an osteogenic factor and a bone resorption
inhibitor.
[0073] In certain embodiments the phosphoglyceride is a
phospholipid. In some embodiments, the phospholipid is a
phosphatidylcholine having fatty acid moieties of at least 14
carbons. In another embodiment, the composition further comprises a
phosphatidylethanolamine having a fatty acid moiety of at least 14
carbons. In another embodiment, the composition further comprises a
sterol. In some embodiments the sterol is cholesterol.
[0074] In another embodiment, the matrix composition is lipid
saturated. "Lipid saturated," as used herein, refers to saturation
of the polymer of the matrix composition with lipids including
phospholipids, in combination with any hydrophobic drug and
targeting moiety present in the matrix, and any other lipids that
may be present. The matrix composition is saturated by whatever
lipids are present. Lipid-saturated matrices of the present
invention exhibit the additional advantage of not requiring a
synthetic emulsifier or surfactant such as polyvinyl alcohol; thus,
compositions of the present invention are typically substantially
free of polyvinyl alcohol. Methods for determining the
polymer:lipid ratio to attain lipid saturation and methods of
determining the degree of lipid saturation of a matrix are
described herein below.
[0075] In another embodiment, the matrix composition is
homogeneous. In another embodiment, the matrix composition is in
the form of a lipid-saturated matrix whose shape and boundaries are
determined by the polymer. In another embodiment, the matrix
composition is in the form of an implant. Preferably, the
non-biocompatible polymer, the phosphatidylethanolamine, and the
sterol are incorporated into the matrix composition. In another
embodiment, the phosphatidylcholine is also incorporated into the
matrix composition. In another embodiment, the antibiotic is also
incorporated into the matrix composition. In another embodiment,
the antibiotic has low water solubility. In another embodiment, the
antibiotic is a hydrophobic antibiotic. In another embodiment, the
antibiotic is an amphipathic antibiotic. In another embodiment, the
composition further comprises a non-steroidal anti-inflammatory
drug (NSAID). In another embodiment, the NSAID as well is
incorporated into the matrix composition. In another embodiment,
the NSAID has low water solubility. Each possibility represents a
separate embodiment of the present invention.
[0076] In one embodiment, the present invention provides a matrix
composition comprising: (a) a non-biodegradable polymer (b) a
sterol; (c) a phosphatidylethanolamine having a fatty acid moiety
of at least 14 carbons; (d) a phosphatidylcholine having a fatty
acid moiety of at least 14 carbons; and (e) an antibiotic or an
antifungal. In another embodiment, the matrix composition is lipid
saturated. Preferably, the polymer, the phosphatidylethanolamine,
and the sterol are incorporated into the matrix composition. In
another embodiment, the phosphatidylcholine is also incorporated
into the matrix composition. In another embodiment, the antibiotic
is also incorporated into the matrix composition. In another
embodiment, the antibiotic has low water solubility. In another
embodiment, the antibiotic is a hydrophobic antibiotic. In another
embodiment, the antibiotic is an amphipathic antibiotic. In another
embodiment, the composition further comprises a non-steroidal
anti-inflammatory drug (NSAID). In another embodiment, the NSAID as
well is incorporated into the matrix composition. In another
embodiment, the NSAID has low water solubility. In another
embodiment, the matrix composition is in the form of a
lipid-saturated matrix whose shape and boundaries are influenced by
the nature of the polymer. In another embodiment, the matrix
composition is in the form of an implant. In another embodiment,
the matrix composition is homogeneous. Each possibility represents
a separate embodiment of the present invention.
[0077] In another embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having fatty acid moieties
of at least 14 carbons; (d) a phosphatidylcholine having fatty acid
moieties of at least 14 carbons; (e) a non-steroidal
anti-inflammatory drug (NSAID). In another embodiment, the matrix
composition is lipid saturated. Preferably, the polyester, the
phosphatidylethanolamine, and the sterol are incorporated into the
matrix composition. In another embodiment, the phosphatidylcholine
is also incorporated into the matrix composition. In another
embodiment, the NSAID is also incorporated into the matrix
composition. In another embodiment, the NSAID has low water
solubility. In another embodiment, the NSAID is a hydrophobic
NSAID. In another embodiment, the NSAID is an amphipathic NSAID. In
another embodiment, the matrix composition is in the form of a
lipid-saturated matrix whose shape and boundaries are determined by
the polymer. In another embodiment, the matrix composition is in
the form of an implant. In another embodiment, the matrix
composition is homogeneous. Each possibility represents a separate
embodiment of the present invention.
[0078] In another embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having fatty acid moieties
of at least 14 carbons; (d) a phosphatidylcholine having fatty acid
moieties of at least 14 carbons; and (e) an osteogenic factor or a
bone resorption inhibitor. In another embodiment, the matrix
composition is lipid saturated. Preferably, the polymer, the
phosphatidylethanolamine, and the sterol are incorporated into the
matrix composition. In another embodiment, the phosphatidylcholine
is also incorporated into the matrix composition. In another
embodiment, the bone resorption inhibitor is also incorporated into
the matrix composition. In another embodiment, the bone resorption
inhibitor has low water solubility. In another embodiment, the bone
resorption inhibitor is a hydrophobic bone resorption inhibitor. In
another embodiment, the bone resorption inhibitor is an amphipathic
bone resorption inhibitor. In another embodiment, the composition
further comprises an NSAID. In another embodiment, the NSAID as
well is incorporated into the matrix composition. In another
embodiment, the matrix composition is in the form of a
lipid-saturated matrix whose shape and boundaries are determined by
the polymer. In another embodiment, the matrix composition is in
the form of an implant. In another embodiment, the matrix
composition is homogeneous. Each possibility represents a separate
embodiment of the present invention.
[0079] In another embodiment, the present invention provides a
matrix composition comprising: (a) non-biodegradable polymer; (b) a
sterol; (c) a phosphatidylethanolamine having fatty acid moieties
of at least 14 carbons; (d) a phosphatidylcholine having fatty acid
moieties of at least 14 carbons; (e) an active agent; and (f) a
targeting moiety capable of interacting with a surface molecule of
a target cell, a target molecule or a target surface. In another
embodiment, the matrix composition is lipid saturated. In another
embodiment, the active agent is selected from the group consisting
of an NSAID, an antibiotic, and a bone resorption inhibitor. In
another embodiment, the polymer and the phospholipid form the
matrix composition that is substantially free of water. In another
embodiment, the active agent and the targeting moiety are
integrated into the lipid vesicle. In another embodiment, the
matrix composition is in the form of a lipid-saturated matrix whose
shape and boundaries are determined by the polymer. In another
embodiment, the matrix composition is in the form of an implant. In
another embodiment, the matrix composition is homogeneous. Each
possibility represents a separate embodiment of the present
invention.
[0080] In another embodiment, the polymer of methods and
compositions of the present invention is associated with the sterol
via hydrogen bonds.
[0081] As provided herein, the matrix composition of methods and
compositions of the present invention is capable of being molded
into three-dimensional configurations of varying thickness and
shape. Accordingly, the matrix formed can be produced to assume a
specific shape including a sphere, cube, rod, tube, sheet, or into
strings. In the case of freeze-drying, the shape is determined by
the shape of a mold or support which may be made of any inert
material and may be in contact with the matrix on all sides, as for
a sphere or cube, or on a limited number of sides as for a sheet.
The matrix may be shaped in the form of body cavities as required
for implant design. Removing portions of the matrix with scissors,
a scalpel, a laser beam or any other cutting instrument can create
any refinements required in the three-dimensional structure. Each
possibility represents a separate embodiment of the present
invention.
[0082] Advantageously, the matrix compositions of the present
invention are prepared by methods which do not involve the
formation of emulsions, and may avoid the use of aqueous media
altogether. The generation of emulsions that are subsequently dried
necessarily results in vesicles or microspheres. In contrast, the
matrices produced without aqueous media form homogeneous liquid
mixtures that can be molded or formed into three dimensional
articles of any shape or can coat the surface of different
substrates. In order to produce molded or coated articles the
mixture of polymer and lipids and active ingredients within the
appropriate selected volatile organic solvents will be used to coat
the desired surface or to fit the desired shape.
[0083] The matrix composition of methods and compositions of the
present invention is capable of coating the surface of different
substrates. Substrates to be coated include materials selected from
the group consisting of carbon fibers, stainless steel,
cobalt-chromium, titanium alloy, tantalum, ceramic and collagen or
gelatin. Specifically, substrates may include any medical devices
such as orthopedic nails, orthopedic screws, orthopedic staples,
orthopedic wires and orthopedic pins used in orthopedic surgery,
metal or polymeric implants used in both orthopedic and periodontal
surgery, bone filler particles and absorbable gelatin sponge. Bone
filler particles can be selected from any one of allogeneic (i.e.,
from human sources), xenogeneic (i.e., from animal sources) and
artificial bone particles.
[0084] According to some embodiments, the matrix composition of the
present invention is useful as a bone graft material. This term
refers to a natural or synthetic material that supports attachment
of new osteoblasts and osteoprogenitor cells or can induce
non-differentiated stem cells or osteoprogenitor cells to
differentiate into osteoblasts. In another embodiment, the bone
graft material is selected from the group consisting of an
allograft, an alloplast, a xenograft, and an autologous bone graft.
In other example the lipid matrix of the present invention can also
be used in conjunction with a collagen membrane or collagen sponge
or gelatin sponge or the like.
[0085] Lipids
[0086] "Phospholipids" are phosphoglycerides having a single
phosphatidyl linkage on a glycerol backbone and fatty acids at the
remaining two positions. However, it is to be understood explicitly
that phosphoglycerides having hydrocarbon chains other than fatty
acid residues including alkyl chains, alkenyl chains or any other
hydrocarbon chain of at least 14 carbons are included within the
scope of the present invention. The linkage may be an ether linkage
instead of an acyl linkage found in phospholipids.
[0087] "Phosphatidylcholine" refers to a phosphoglyceride having a
phosphorylcholine head group. Phosphatidylcholine compounds, in
another embodiment, have the following structure:
##STR00001##
[0088] The R and R' moieties are fatty acids, typically naturally
occurring fatty acids or derivatives of naturally occurring fatty
acids. In some embodiments, the fatty acid moieties are saturated
fatty acid moieties. In some embodiments, the fatty acid moieties
are unsaturated fatty acid moieties. "Saturated", refers to the
absence of a double bond in the hydrocarbon chain. In another
embodiment, the fatty acid moieties have at least 14 carbon atoms.
In another embodiment, the fatty acid moieties have 16 carbon
atoms. In another embodiment, the fatty acid moieties have 18
carbon atoms. In another embodiment, the fatty acid moieties have
16-18 carbon atoms. In another embodiment, the fatty acid moieties
are chosen such that the gel-to-liquid-crystal transition
temperature of the resulting matrix is at least 40.degree. C. In
another embodiment, the fatty acid moieties are both palmitoyl. In
another embodiment, the fatty acid moieties are both stearoyl. In
another embodiment, the fatty acid moieties are both arachidoyl. In
another embodiment, the fatty acid moieties are palmitoyl and
stearoyl. In another embodiment, the fatty acid moieties are
palmitoyl and arachidoyl. In another embodiment, the fatty acid
moieties are arachidoyl and stearoyl. Each possibility represents a
separate embodiment of the present invention.
[0089] In another embodiment, the phosphatidylcholine is a
naturally-occurring phosphatidylcholine. In another embodiment, the
phosphatidylcholine is a synthetic phosphatidylcholine. In another
embodiment, the phosphatidylcholine contains a naturally-occurring
distribution of isotopes. In another embodiment, the
phosphatidylcholine is a deuterated phosphatidylcholine. In another
embodiment, the phosphatidylcholine is labeled with any other
isotope or label. Preferably, the phosphatidylcholine is a
symmetric phosphatidylcholine (i.e. a phosphatidylcholine wherein
the two fatty acid moieties are identical). In another embodiment,
the phosphatidylcholine is an asymmetric phosphatidylcholine.
[0090] Non-limiting examples of phosphatidylcholines are
1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC),
dioleoyl-phosphatidylcholine (DOPC),
1-palmitoyl-2-oleoyl-phosphatidylcholine, and phosphatidylcholines
modified with any of the fatty acid moieties enumerated
hereinabove. In another embodiment, the phosphatidylcholine is
selected from the group consisting of DSPC and DOPC, and
1-palmitoyl-2-oleoyl-phosphatidylcholine.
[0091] In another embodiment, the phosphatidylcholine is any other
phosphatidylcholine known in the art. Each phosphatidylcholine
represents a separate embodiment of the present invention.
[0092] "Phosphatidylethanolamine" refers to a phosphoglyceride
having a phosphoryl ethanolamine head group.
Phosphatidylethanolamine compounds, in another embodiment, have the
following structure:
##STR00002##
[0093] The R.sub.1 and R.sub.2 moieties are fatty acids, typically
naturally occurring fatty acids or derivatives of naturally
occurring fatty acids. In another embodiment, the fatty acid
moieties are saturated fatty acid moieties. "Saturated" in another
embodiment, refers to the absence of a double bond in the
hydrocarbon chain. In another embodiment, the fatty acid moieties
have at least 14 carbon atoms. In another embodiment, the fatty
acid moieties have at least 16 carbon atoms. In another embodiment,
the fatty acid moieties have 14 carbon atoms. In another
embodiment, the fatty acid moieties have 16 carbon atoms. In
another embodiment, the fatty acid moieties have 18 carbon atoms.
In another embodiment, the fatty acid moieties have 14-18 carbon
atoms. In another embodiment, the fatty acid moieties have 14-16
carbon atoms. In another embodiment, the fatty acid moieties have
16-18 carbon atoms. In another embodiment, the fatty acid moieties
are chosen such that the gel-to-liquid-crystal transition
temperature of the resulting matrix is at least 40.degree. C. In
another embodiment, the fatty acid moieties are both myristoyl. In
another embodiment, the fatty acid moieties are both palmitoyl. In
another embodiment, the fatty acid moieties are both stearoyl. In
another embodiment, the fatty acid moieties are both arachidoyl. In
another embodiment, the fatty acid moieties are myristoyl and
stearoyl. In another embodiment, the fatty acid moieties are
myristoyl and arachidoyl. In another embodiment, the fatty acid
moieties are myristoyl and palmitoyl. In another embodiment, the
fatty acid moieties are palmitoyl and stearoyl. In another
embodiment, the fatty acid moieties are palmitoyl and arachidoyl.
In another embodiment, the fatty acid moieties are arachidoyl and
stearoyl. Each possibility represents a separate embodiment of the
present invention.
[0094] In another embodiment, the phosphatidylethanolamine is a
naturally-occurring phosphatidylethanolamine. In another
embodiment, the phosphatidylethanolamine is a synthetic
phosphatidylethanolamine. In another embodiment, the
phosphatidylethanolamine is a deuterated phosphatidylethanolamine.
In another embodiment, the phosphatidylethanolamine is labeled with
any other isotope or label. In another embodiment, the
phosphatidylethanolamine contains a naturally-occurring
distribution of isotopes. Preferably, the phosphatidylethanolamine
is a symmetric phosphatidylethanolamine. In another embodiment, the
phosphatidylethanolamine is an asymmetric
phosphatidylethanolamine.
[0095] Non-limiting examples of phosphatidylethanolamines are
dimethyl dimyristoyl phosphatidylethanolamine (DMPE) and
dipalmitoyl-phosphatidylethanolamine (DPPE), and
phosphatidylethanolamines modified with any of the fatty acid
moieties enumerated hereinabove. In another embodiment, the
phosphatidylethanolamine is selected from the group consisting of
DMPE and DPPE.
[0096] In another embodiment, the phosphatidylethanolamine is any
other phosphatidylethanolamine known in the art. Each
phosphatidylethanolamine represents a separate embodiment of the
present invention.
[0097] "Sterol" in one embodiment refers to a steroid with a
hydroxyl group at the 3-position of the A-ring. In another
embodiment, the term refers to a steroid having the following
structure:
##STR00003##
[0098] In another embodiment, the sterol of methods and
compositions of the present invention is a zoosterol. In another
embodiment, the sterol is cholesterol:
##STR00004##
[0099] In another embodiment, the sterol is any other zoosterol
known in the art. In another embodiment, the moles of sterol are up
to 40% of the moles of total lipids present. In another embodiment,
the sterol is incorporated into the matrix composition. Each
possibility represents a separate embodiment of the present
invention.
[0100] In another embodiment, the cholesterol is present in an
amount of 10-50 percentage of the total weight of lipid content of
the matrix composition. In another embodiment, the weight
percentage is 20-50%. In another embodiment, the weight percentage
is 10-40%. In another embodiment, the weight percentage is 30-50%.
In another embodiment, the weight percentage is 20-60%. In another
embodiment, the weight percentage is 25-55%. In another embodiment,
the weight percentage is 35-55%. In another embodiment, the weight
percentage is 30-60%. In another embodiment, the weight percentage
is 30-55%. In another embodiment, the weight percentage is 20-50%.
In another embodiment, the weight percentage is 25-55%. Each
possibility represents a separate embodiment of the present
invention.
[0101] In another embodiment, a composition of the present
invention further comprises a lipid other than phosphatidylcholine,
phosphatidylethanolamine, or a sterol. In another embodiment, the
additional lipid is a phosphoglyceride. In another embodiment, the
additional lipid is selected from the group consisting of a
phosphatidylserine, a phosphatidylglycerol, and a
phosphatidylinositol. In another embodiment, the additional lipid
is selected from the group consisting of a phosphatidylserine, a
phosphatidylglycerol, a phosphatidylinositol, and a sphingomyelin.
In another embodiment, a combination of any 2 or more of the above
additional lipids is present. In another embodiment, the polymer,
phosphatidylcholine, phosphatidylethanolamine, sterol, and
additional lipid(s) are all incorporated into the matrix
composition. Each possibility represents a separate embodiment of
the present invention.
[0102] In another embodiment, phosphatidylcholine(s) (PC) compose
at least 30% of the total lipid content of the matrix composition.
In another embodiment, PC(s) compose at least 35% of the total
lipid content. In another embodiment, PC(s) compose at least 40% of
the total lipid content. In another embodiment, PC(s) compose at
least 45% of the total lipid content. In another embodiment, PC(s)
compose at least 50% of the total lipid content. In another
embodiment, PC(s) compose at least 55% of the total lipid content.
In another embodiment, PC(s) compose at least 60% of the total
lipid content. In another embodiment, PC(s) compose at least 65% of
the total lipid content. In another embodiment, PC(s) compose at
least 70% of the total lipid content. In another embodiment, PC(s)
compose at least 75% of the total lipid content. In another
embodiment, PC(s) compose at least 80% of the total lipid content.
In another embodiment, PC(s) compose at least 85% of the total
lipid content. In another embodiment, PC(s) compose at least 90% of
the total lipid content. In another embodiment, PC(s) compose at
least 95% of the total lipid content. In another embodiment, PC(s)
compose over 95% of the total lipid content. Each possibility
represents a separate embodiment of the present invention.
[0103] In another embodiment, a composition of the present
invention further comprises a phosphatidylserine.
"Phosphatidylserine" refers to a phosphoglyceride having a
phosphorylserine head group. Phosphatidylserine compounds, in
another embodiment, have the following structure:
##STR00005##
[0104] The R.sub.1 and R.sub.2 moieties are fatty acids, typically
naturally occurring fatty acids or derivatives of naturally
occurring fatty acids. In another embodiment, the fatty acid
moieties are saturated fatty acid moieties. In another embodiment,
the fatty acid moieties have at least 14 carbon atoms. In another
embodiment, the fatty acid moieties have at least 16 carbon atoms.
In another embodiment, the fatty acid moieties are chosen such that
the gel-to-liquid-crystal transition temperature of the resulting
matrix is at least 40.degree. C. In another embodiment, the fatty
acid moieties are both myristoyl. In another embodiment, the fatty
acid moieties are both palmitoyl. In another embodiment, the fatty
acid moieties are both stearoyl. In another embodiment, the fatty
acid moieties are both arachidoyl. In another embodiment, the fatty
acid moieties are myristoyl and stearoyl. In another embodiment,
the fatty acid moieties are a combination of two of the above fatty
acid moieties.
[0105] In another embodiment, the phosphatidylserine is a
naturally-occurring phosphatidyl serine. In another embodiment, the
phosphatidylserine is a synthetic phosphatidyl serine. In another
embodiment, the phosphatidylserine is a deuterated phosphatidyl
serine. In another embodiment, the phosphatidylserine is labeled
with any other isotope or label. In another embodiment, the
phosphatidylserine contains a naturally-occurring distribution of
isotopes. In another embodiment, the phosphatidylserine is a
symmetric phosphatidylserine. In another embodiment, the
phosphatidylserine is an asymmetric phosphatidylserine.
[0106] Non-limiting examples of phosphatidylserines are
phosphatidylserines modified with any of the fatty acid moieties
enumerated hereinabove. In another embodiment, the
phosphatidylserine is any other phosphatidylserine known in the
art. Each phosphatidylserine represents a separate embodiment of
the present invention.
[0107] In another embodiment, a composition of the present
invention further comprises a phosphatidylglycerol.
"Phosphatidylglycerol" refers to a phosphoglyceride having a
phosphoryl glycerol head group. Phosphatidylglycerol compounds, in
another embodiment, have the following structure:
##STR00006##
[0108] The 2 bonds to the left are connected to fatty acids,
typically naturally occurring fatty acids or derivatives of
naturally occurring fatty acids. In another embodiment, the
phosphatidylglycerol is a naturally-occurring phosphatidylglycerol.
In another embodiment, the phosphatidylglycerol is a synthetic
phosphatidyl glycerol. In another embodiment, the
phosphatidylglycerol is a deuterated phosphatidylglycerol. In
another embodiment, the phosphatidylglycerol is labeled with any
other isotope or label. In another embodiment, the
phosphatidylglycerol contains a naturally-occurring distribution of
isotopes. In another embodiment, the phosphatidylglycerol is a
symmetric phosphatidylglycerol. In another embodiment, the
phosphatidylglycerol is an asymmetric phosphatidylglycerol. In
another embodiment, the term includes diphosphatidylglycerol
compounds having the following structure:
##STR00007##
[0109] The R and R' moieties are fatty acids, typically naturally
occurring fatty acids or derivatives of naturally occurring fatty
acids. In another embodiment, the fatty acid moieties are saturated
fatty acid moieties. In another embodiment, the fatty acid moieties
have at least 14 carbon atoms. In another embodiment, the fatty
acid moieties have at least 16 carbon atoms. In another embodiment,
the fatty acid moieties are chosen such that the
gel-to-liquid-crystal transition temperature of the resulting
matrix is at least 40.degree. C. In another embodiment, the fatty
acid moieties are both myristoyl. In another embodiment, the fatty
acid moieties are both palmitoyl. In another embodiment, the fatty
acid moieties are both stearoyl. In another embodiment, the fatty
acid moieties are both arachidoyl. In another embodiment, the fatty
acid moieties are myristoyl and stearoyl. In another embodiment,
the fatty acid moieties are a combination of two of the above fatty
acid moieties.
[0110] Non-limiting examples of phosphatidylglycerols are
phosphatidylglycerols modified with any of the fatty acid moieties
enumerated hereinabove. In another embodiment, the
phosphatidylglycerol is any other phosphatidylglycerol known in the
art. Each phosphatidylglycerol represents a separate embodiment of
the present invention.
[0111] In another embodiment, a composition of the present
invention further comprises a phosphatidylinositol. "Phosphatidyl
inositol" refers to a phosphoglyceride having a phosphorylinositol
head group. Phosphatidylinositol compounds, in another embodiment,
have the following structure:
##STR00008##
[0112] The R.sub.1 and R.sub.2 moieties are fatty acids, typically
naturally occurring fatty acids or derivatives of naturally
occurring fatty acids. In another embodiment, the fatty acid
moieties are saturated fatty acid moieties. In another embodiment,
the fatty acid moieties have at least 14 carbon atoms. In another
embodiment, the fatty acid moieties have at least 16 carbon atoms.
In another embodiment, the fatty acid moieties are chosen such that
the gel-to-liquid-crystal transition temperature of the resulting
matrix is at least 40.degree. C. In another embodiment, the fatty
acid moieties are both myristoyl. In another embodiment, the fatty
acid moieties are both palmitoyl. In another embodiment, the fatty
acid moieties are both stearoyl. In another embodiment, the fatty
acid moieties are both arachidoyl. In another embodiment, the fatty
acid moieties are myristoyl and stearoyl. In another embodiment,
the fatty acid moieties are a combination of two of the above fatty
acid moieties.
[0113] In another embodiment, the phosphatidyl inositol is a
naturally-occurring phosphatidylinositol. In another embodiment,
the phosphatidylinositol is a synthetic phosphatidylinositol. In
another embodiment, the phosphatidylinositol is a deuterated
phosphatidylinositol. In another embodiment, the
phosphatidylinositol is labeled with any other isotope or label. In
another embodiment, the phosphatidylinositol contains a
naturally-occurring distribution of isotopes. In another
embodiment, the phosphatidylinositol is a symmetric
phosphatidylinositol. In another embodiment, the
phosphatidylinositol is an asymmetric phosphatidylinositol.
[0114] Non-limiting examples of phosphatidylinositols are
phosphatidylinositols modified with any of the fatty acid moieties
enumerated hereinabove. In another embodiment, the
phosphatidylinositol is any other phosphatidylinositol known in the
art. Each phosphatidylinositol represents a separate embodiment of
the present invention.
[0115] In another embodiment, a composition of the present
invention further comprises a sphingolipid. In another embodiment,
the sphingolipid is ceramide. In another embodiment, the
sphingolipid is a sphingomyelin. "Sphingomyelin" refers to a
sphingosine-derived phospholipid. Sphingomyelin compounds, in
another embodiment, have the following structure:
##STR00009##
[0116] The R moiety is a fatty acid, typically a naturally
occurring fatty acid or a derivative of a naturally occurring fatty
acid. In another embodiment, the sphingomyelin is a
naturally-occurring sphingomyelin. In another embodiment, the
sphingomyelin is a synthetic sphingomyelin. In another embodiment,
the sphingomyelin is a deuterated sphingomyelin. In another
embodiment, the sphingomyelin is labeled with any other isotope or
label. In another embodiment, the sphingomyelin contains a
naturally-occurring distribution of isotopes.
[0117] In another embodiment, the fatty acid moiety of a
sphingomyelin of methods and compositions of the present invention
has at least 14 carbon atoms. In another embodiment, the fatty acid
moiety has at least 16 carbon atoms. In another embodiment, the
fatty acid moiety is chosen such that the gel-to-liquid-crystal
transition temperature of the resulting matrix is at least
40.degree. C.
[0118] Non-limiting examples of sphingomyelins are sphingomyelins
modified with any of the fatty acid moieties enumerated
hereinabove. In another embodiment, the sphingomyelin is any other
sphingomyelin known in the art. Each sphingomyelin represents a
separate embodiment of the present invention.
[0119] "Ceramide" refers to a compound having the structure:
##STR00010##
[0120] The R moiety is a fatty acid typically naturally occurring
fatty acid or derivatives of naturally occurring fatty acids. In
another embodiment, the fatty acid is a longer-chain (to C.sub.24
or greater). In another embodiment, the fatty acids are saturated
fatty acids. In another embodiment, the fatty acids are monoenoic
fatty acids. In another embodiment, the fatty acids are n-9
monoenoic fatty acids. In another embodiment, the fatty acids
contain a hydroxyl group in position 2. In another embodiment, the
fatty acids are other suitable fatty acids known in the art. In
another embodiment, the ceramide is a naturally-occurring ceramide.
In another embodiment, the ceramide is a synthetic ceramide. In
another embodiment, the ceramide is incorporated into the matrix
composition. Each possibility represents a separate embodiment of
the present invention.
[0121] Each sphingolipid represents a separate embodiment of the
present invention.
[0122] In another embodiment, a composition of the present
invention further comprises a pegylated lipid. In another
embodiment, the PEG moiety has a MW of 500-5000 daltons. In another
embodiment, the PEG moiety has any other suitable MW. Non-limiting
examples of suitable PEG-modified lipids include PEG moieties with
a methoxy end group, e.g. PEG-modified phosphatidylethanolamine and
phosphatidic acid (structures A and B), PEG-modified
diacylglycerols and dialkylglycerols (structures C and D),
PEG-modified dialkylamines (structure E) and PEG-modified
1,2-diacyloxypropan-3-amines (structure F) as depicted below. In
another embodiment, the PEG moiety has any other end group used in
the art. In another embodiment, the pegylated lipid is selected
from the group consisting of a PEG-modified
phosphatidylethanolamine, a PEG-modified phosphatidic acid, a
PEG-modified diacylglycerol, a PEG-modified dialkylglycerol, a
PEG-modified dialkylamine, and a PEG-modified
1,2-diacyloxypropan-3-amine. In another embodiment, the pegylated
lipid is any other pegylated phospholipid known in the art. Each
possibility represents a separate embodiment of the present
invention.
##STR00011##
[0123] Preferably, the pegylated lipid is present in an amount of
less than 10 mole percent of total lipids in the matrix
composition. In another embodiment, the percentage is less than 9
mole % of the total lipids. In another embodiment, the percentage
is less than 8 mole %. In another embodiment, the percentage is
less than 7 mole %. In another embodiment, the percentage is less
than 6 mole %. In another embodiment, the percentage is less than 5
mole %. In another embodiment, the percentage is less than 4 mole
%. In another embodiment, the percentage is less than 3 mole %. In
another embodiment, the percentage is less than 2 mole %. In
another embodiment, the percentage is less than 1 mole %. Each
possibility represents a separate embodiment of the present
invention.
[0124] Polymers
[0125] According to some embodiments, the non-biodegradable polymer
may be selected yet not limited to polyethylene glycol,
polyethylene glycol (PEG) acrylate, polymethacrylates (e.g. PEG
methacrylate, polymethylmethacrylate, polyethylmethacrylate,
polybutylmethacrylate, poly-2-ethylhexylmethacrylate,
polylaurylmethacrylate, polyhydroxylethyl methacrylate),
poly-methylacrylate, 2-methacryloyloxyethylphosphorylcholine (MPC),
polystyrene, derivatized polystyrene, polylysine, poly
N-ethyl-4-vinyl-pyridinium bromide, silicone, ethylene-vinyl
acetate copolymers, polyethylenes, polypropylenes,
polytetrafluoroethylenes, polyurethanes, polyacrylates, polyvinyl
acetate, ethylene vinyl acetate, polyethylene, polyvinyl chloride,
polyvinyl fluoride, copolymers of polymers of ethylene-vinyl
acetates and acyl substituted cellulose acetates, poly(vinyl
imidazole), chlorosulphonate polyolefins, polyethylene oxide, and
mixtures thereof.
[0126] According to particulate embodiment, the non-biodegradable
polymer is polyethylene glycol. Polyethylene glycol refers to an
oligomer or polymer of ethylene oxide. According to particular
embodiment, the non-biodegradable polymer comprises polyethylene
glycol having a molecular weight from about 1000 to about 20000;
alternatively, between 2000 to about 10000. According to some
exemplary embodiments, the non-biodegradable polymer is PEG having
a molecular weight between about 4000 and about 8000.
[0127] According to some embodiments, the matrix composition may
further comprise a biodegradable polymer. According to some
embodiments, the matrix composition may comprise a biodegradable
polymer other than a polyester. According to some other
embodiments, the biodegradable polymer is selected from the group
consisting of poly(caprolactone), polycarbonates, polyesteramides,
polyanhydrides, poly(amino acid)s, polycyanoacrylates, polyamides,
polyacetals, poly(ether ester)s, poly(dioxanone)s, poly(alkylene
alkylate)s, biodegradable polyurethanes, blends and copolymers
thereof. According to some other embodiments, the biodegradable
polymer is a polyester. Non limiting examples of polyesters include
PLA (polylactic acid), PGA (polyglycolic acid) and PLGA
(poly(lactic-co-glycolic acid). According to some embodiment, the
PLGA has a 1:1 lactic acid/glycolic acid ratio. In another
embodiment, the ratio is 60:40. In another embodiment, the ratio is
70:30. In another embodiment, the ratio is 80:20. In another
embodiment, the ratio is 90:10. In another embodiment, the ratio is
95:5. In another embodiment, the ratio is another ratio appropriate
for an extended in vivo release profile, as defined herein. In
another embodiment, the ratio is 50:50. The PLGA may be either a
random or block copolymer. Each possibility represents a separate
embodiment of the present invention. In another embodiment, the
biodegradable polyester may be selected from the group consisting
of a polycaprolactone, a polyhydroxyalkanoate, a
polypropylenefumarate, a polyorthoester, a polyanhydride, and a
polyalkylcyanoacrylate, provided that the polyester contains a
hydrogen bond acceptor moiety. In another embodiment, the
biodegradable polyester is a block copolymer containing a
combination of any two monomers selected from the group consisting
of a PLA, PGA, a PLGA, polycaprolactone, a polyhydroxyalkanoate, a
polypropylenefumarate, a polyorthoester, a polyanhydride, and a
polyalkylcyanoacrylate. In another embodiment, the biodegradable
polyester is a random copolymer containing a combination of any two
of the monomers listed above. Each possibility represents a
separate embodiment of the present invention.
[0128] The molecular weight (MW) of a non-biodegradable polymer of
methods and compositions of the present invention is, in another
embodiment, between about 1-40 KDa. In another embodiment, the MW
is between about 4-50 KDa. In another embodiment, the MW is between
about 15-40 KDa. In another embodiment, the MW is between about
20-40 KDa. In another embodiment, the MW is between about 15-35
KDa. In another embodiment, the MW is between about 10-35 KDa. In
another embodiment, the MW is between about 10-30 KDa. In another
embodiment, the MW is between about 1-10 KDa. In another
embodiment, the MW is between about 1-5 KDa. In another embodiment,
the MW is between about 2-5 KDa. In another embodiment, a mixture
of non-biodegradable polymers of different MW is utilized. In
another embodiment, a mixture of non-biodegradable polymer and a
biodegradable polyer of different MW may be utilized. In another
embodiment, the different polymers both have a MW in one of the
above ranges. Each possibility represents a separate embodiment of
the present invention.
[0129] Antibiotics
[0130] The antibiotic of methods and compositions of the present
invention is, in another embodiment, doxycycline. In another
embodiment, the antibiotic is a hydrophobic tetracycline.
Non-limiting examples of hydrophobic tetracycline are
6-demethyl-6-deoxytetracycline, 6-methylene tetracycline,
minocycline (also known as
7-dimethylamino-6-demethyl-6-deoxytetracycline), and
13-phenylmercapto-a-6-deoxy-tetracycline. In another embodiment,
the antibiotic is selected from the group consisting of
doxycycline, tetracycline, and minocycline. In another embodiment,
the antibiotic is integrated into the matrix composition.
[0131] In another embodiment, the antibiotic is selected from the
group consisting of amoxicillin, amoxicillin/clavulanic acid,
penicillin, metronidazole, clindamycine, chlortetracycline,
demeclocycline, oxytetracycline, amikacin, gentamicine, kanamycin,
neomycin, netilmicin, streptomycin, tobramycin, cefadroxil,
cefazolin, cephalexin, cephalothin, cephapirin, cephradine,
cefaclor, cefamandole, cefametazole, cefonicid, cefotetan,
cefoxitine, cefpodoxime, cefprozil, cefuroxime, cefdinir, cefixime,
cefoperazone, cefotaxime, ceftazidime, ceftibuten, ceftizoxime,
ceftriaxone, cefepime, azithromycin, clarithromycin, dirithromycin,
erythromycin, lincomycin, troleandomycin, bacampicillin,
carbenicillin, cloxacillin, dicloxacillin, meticillin, mezlocillin,
nafcillin, oxacillin, piperacillin, ticarcillin, cinoxacin,
ciprofloxacin, enoxacin, grepafloxacin, levofloxacin, lomefloxacin,
nalidixic acid, norfloxacin, ofloxacin, sparfloxacin,
sulfisoxazole, sulfacytine, sulfadiazine, sulfamethoxazole,
sulfisoxazole, dapson, aztreonam, bacitracin, capreomycin,
chloramphenicol, clofazimine, colistimethate, colistin,
cycloserine, fosfomycin, furazolidone, methenamine, nitrofurantoin,
pentamidine, rifabutin, rifampin, spectinomycin, trimethoprim,
trimetrexate glucuronate, and vancomycin.
[0132] In another embodiment, the biologically active ingredient is
an antiseptic drug such as chlorhexidine.
[0133] Each antibiotic represents a separate embodiment of the
present invention.
[0134] NSAID's
[0135] Any suitable NSAID may be integrated into the matrix
composition for sustained and/or controlled release. The NSAID of
methods and compositions of the present invention is, in one
embodiment, flurbiprofen. In another embodiment, the NSAID is
selected from the group consisting of ibuprofen and flurbiprofen.
In another embodiment, the NSAID is selected from the group
consisting of ibuprofen, flurbiprofen, aminosalicylate sodium,
choline magnesium trisalicylate, choline salicylate, diclofenac,
diflunisal, etodolac, fenoprofen, indomethacin, ketoprofen, ketolac
tromethamine, magnesium salicylate, meclofenamate, mefenamic acid,
nabumetone, naproxen, oxaprozin, oxyphenbutazone, piroxicam,
salsalate, sulindac, tolmetin.
[0136] Each NSAID represents a separate embodiment of the present
invention.
[0137] Steroids
[0138] In another embodiment, the active agent of methods and
compositions of the present invention is a steroid. According to
one embodiment the steroid is a steroidal anti-inflammatory drug.
Non limiting examples of steroidal anti-inflammatory drugs (SAIDs)
to be used in the formulations of the present invention include,
but are not limited to, Corticosteroids such as: betamethasone,
betamethasone valerate, cortisone, dexamethasone, dexamethasone
21-phosphate, fludrocortisone, flumethasone, fluocinonide,
fluocinonide desonide, fluocinolone, fluocinolone acetonide,
fluocortolone, halcinonide, halopredone, hydrocortisone,
hydrocortisone 17-valerate, hydrocortisone 17-butyrate,
hydrocortisone 21-acetate methylprednisolone, prednisolone,
prednisolone 21-phosphate, prednisone, triamcinolone, triamcinolone
acetonide, cortodoxone, fluoracetonide, fludrocortisone,
difluorsone diacetate, flurandrenolone acetonide, medrysone,
amcinafel, amcinafide, betamethasone and its other esters,
chloroprednisone, clorcortelone, descinolone, desonide,
dichlorisone, difluprednate, flucloronide, flumethasone,
flunisolide, flucortolone, fluoromethalone, fluperolone,
fluprednisolone, meprednisone, methylmeprednisolone, paramethasone,
cortisone acetate, hydrocortisone cyclopentylpropionate,
cortodoxone, flucetonide, fludrocortisone acetate, flurandrenolone
acetonide, medrysone, amcinafal, amcinafide, betamethasone,
betamethasone benzoate, chloroprednisone acetate, clocortolone
acetate, descinolone acetonide, desoximetasone, dichlorisone
acetate, difluprednate, flucloronide, flumethasone pivalate,
flunisolide acetate, fluperolone acetate, fluprednisolone valerate,
paramethasone acetate, prednisolamate, prednival, triamcinolone
hexacetonide, cortivazol, formocortal and nivazol.
[0139] Anti-Cancer Agents
[0140] As referred to herein, the term "anti-cancer agent" refers
to any type of agent that may be used in the treatment of cancer
and/or cancer related conditions. The anti-cancer reagent may
include any naturally occurring or synthetically produced molecule
that is capable of affecting directly or indirectly the growth
and/or viability of cancer cells, cancer tumor, and/or cancer
related conditions and symptoms. The anti-cancer agent may include,
for example, a naturally occurring protein or peptide, a modified
protein or peptide, a recombinant protein, a chemically synthesized
protein or peptide, a low oral bioavailability protein or peptide,
a chemical molecule, a synthetic chemical molecule, a
chemotherapeutic drug, a biologically therapeutic drug, and the
like, or any combination thereof. The anti-cancer reagent may be
cytotoxic (toxic to cells) and/or cytostatic (suppress cell growth)
and/or antiproliferative to the cancer cells and may exert its
effect on cancer cells directly and/or indirectly. According to
some embodiments, the anti-cancer reagent may be administered alone
and/or in combination and/or before and/or after one or more
additional cancer treatments. The additional cancer treatment may
include such treatments as, but not limited to: chemotherapy (use
of drugs to affect the cancer cells), radiotherapy (use of
high-energy radiation of various sources to affect the cancer
cells); biological therapy (a therapy which helps the immune system
fight cancer); surgical procedures (surgical removal of the
cancerous tumor); gene therapy; bone marrow transplantation; any
other therapy known in the art, or any combination thereof.
[0141] Non limiting examples of anti-cancer reagents and
chemotherapeutic drugs may include such drugs as, but not limited
to: Alkaloids, such as, but not limited to: Docetaxel, Etoposide,
Irinotecan, Paclitaxel, Teniposide, Topotecan, Vinblastine,
Vincristine, Vindesine; Alkylating agents, such as, but not limited
to: Busulfan, Improsulfan, Piposulfan, Benzodepa, Carboquone,
Meturedepa, Uredepa, Altretamine, triethylenemelamine,
Triethylenephosphoramide, Triethylenethiophosphoramide,
Chlorambucil, Chloranaphazine, Cyclophosphamide, Estramustine,
Ifosfamide, Mechlorethamine, Mechlorethamine Oxide Hcl, Melphalan,
Novemebichin, Perfosfamide Phenesterine, Prednimustine,
Trofosfamide, Uracil Mustard, Carmustine, Chlorozotocin,
Fotemustine, Lomustine, Nimustine, Semustine Ranimustine,
Dacarbazine, Mannomustine, Mitobronitol, Mitolactol, Pipobroman,
Temozolomide; Antibiotics and analogs, such as, but not limited to:
Aclacinomycins, Actinomycins, Anthramycin, Azaserine, Bleomycins,
Cactinomycin, Carubicin, Carzinophilin, Cromomycins, Dactinomycins,
Daunorubicin, 6-Diazo-5-oxo-L-norleucine, Doxorubicin, Epirubicin,
Idarubicin, Menogaril, Mitomycins, Mycophenolic Acid, Nogalamycine,
Olivomycins, Peplomycin, Pirarubicin, Plicamycin, Porfiromycin,
Puromycine, Streptonigrin, Streptozocin, Tubercidin, Zinostatin,
Zorubicin; Antimetabolites, such as, but not limited to:
Denopterin, Edatrexate, Methotrexate, Piritrexim, Pteropterin,
Tomudex, Trimetrexate, Cladridine, Fludarabine, 6-Mercaptopurine,
Pentostatine Thiamiprine, Thioguanine, Ancitabine, Azacitidine,
6-Azauridine, Carmofur, Cytarabine, Doxifluridine, Emitefur,
Floxuridine, Fluorouracil, Gemcitabine, Tegafur; Platinum
complexes, such as, but not limited to: Caroplatin, Cisplatin,
Miboplatin, Oxaliplatin; alkylators including, but not limited to,
busulfan (Myleran, Busulfex), chlorambucil (Leukeran), ifosfamide
(with or without MESNA), cyclophosphamide (Cytoxan, Neosar),
glufosfamide, melphalan, L-PAM (Alkeran), dacarbazine (DTIC-Dome),
and temozolamide (Temodar); anthracyclines, including, but not
limited to doxorubicin (Adriamycin, Doxil, Rubex), mitoxantrone
(Novantrone), idarubicin (Idamycin), valrubicin (Valstar), and
epirubicin (Ellence); antibiotics, including, but not limited to,
dactinomycin, actinomycin D (Cosmegen), bleomycin (Blenoxane),
daunorubicin, and daunomycin (Cerubidine, DanuoXome); aromatase
inhibitors, including, but not limited to anastrozole (Arimidex)
and letroazole (Femara); bisphosphonates, including, but not
limited to zoledronate (Zometa); cyclo-oxygenase inhibitors,
including, but not limited to, celecoxib (Celebrex); estrogen
receptor modulators including, but not limited to tamoxifen
(Nolvadex) and fulvestrant (Faslodex); folate antagonists
including, but not limited to methotrexate and tremetrexate;
inorganic aresenates including, but not limited to arsenic trioxide
(Trisenox); microtubule inhibitors (e.g. taxanes) including, but
not limited to vincristine (Oncovin), vinblastine (Velban),
paclitaxel (Taxol, Paxene), vinorelbine (Navelbine), epothilone B
or D or a derivative of either, and discodermolide or its
derivatives, nitrosoureas including, but not limited to
procarbazine (Matulane), lomustine, CCNU (CeeBU), carmustine (BCNU,
BiCNU, Gliadel Wafer), and estramustine (Emcyt); nucleoside analogs
including, but not limited to mercaptopurine, 6-MP (Purinethol),
fluorouracil, 5-FU (Adrucil), thioguanine, 6-TG (Thioguanine),
hydroxyurea (Hydrea), cytarabine (Cytosar-U, DepoCyt), floxuridine
(FUDR), fludarabine (Fludara), pentostatin (Nipent), cladribine
(Leustatin, 2-CdA), gemcitabine (Gemzar), and capecitabine
(Xeloda); osteoclast inhibitors including, but not limited to
pamidronate (Aredia); platinum containing compounds including, but
not limited to cisplatin (Platinol) and carboplatin (Paraplatin);
retinoids including, but not limited to tretinoin, ATRA (Vesanoid),
alitretinoin (Panretin), and bexarotene (Targretin); topoisomerase
1 inhibitors including, but not limited to topotecan (Hycamtin) and
irinotecan (Camptostar); topoisomerase 2 inhibitors including, but
not limited to etoposide, VP-16 (Vepesid), teniposide, VM-26
(Vumon), and etoposide phosphate (Etopophos); tyrosine kinase
inhibitors including, but not limited to imatinib (Gleevec);
various other proteins including monoclonal antibodies, peptides
and enzymes, various other molecules, such as, for example, Super
Oxide dismutase (SOD), leptin; flavanoids; or any combinations
thereof.
[0142] Non limiting examples of anti-cancer agents and biological
therapies that may be used according to some embodiments, may
include, such therapies and molecules as, but not limited to:
administration of an immunomodulatory molecule, such as, for
example, a molecule selected from the group consisting of tumor
antigens, antibodies, cytokines (such as, for example, interleukins
(such as, for example, interleukin 2, interleukin 4, interleukin
12), interferons (such as, for example, interferon El interferon D,
interferon alpha), tumor necrosis factor (TNF), granulocyte
macrophage colony stimulating factor (GM-CSF), macrophage colony
stimulating factor (M-CSF), and granulocyte colony stimulating
factor (G-CSF)), tumor suppressor genes, chemokines, complement
components, complement component receptors, immune system accessory
molecules, adhesion molecules, adhesion molecule receptors, agents
affecting cell bioenergetics, or any combinations thereof.
[0143] Osteogenic Factors
[0144] In another embodiment, the active agent of methods and
compositions of the present invention is a compound which induces
or stimulates the formation of bone. In another embodiment the
active agent is osteogenic factor. In another embodiment, the
osteogenic factor refers to any peptide, polypeptide, protein or
any other compound or composition which induces or stimulates the
formation of bone. In another embodiment, the osteogenic factor
induces differentiation of bone repair cells into bone cells, such
as osteoblasts or osteocytes. In another embodiment the osteogenic
factor is selected from the group consisting of TGF-beta, BMP and
FGF. In another embodiment the osteogenic factor is encapsulated
within the matrix composition of the present invention in a
concentration sufficient to induce differentiation of bone repair
cells into bone cells which form bone.
[0145] Bone Resorption Inhibitors
[0146] In another embodiment, the active agent of methods and
compositions of the present invention is a compound useful for
supporting bone recovery. In another embodiment, the active agent
is a bone resorption inhibitor. In another embodiment, the active
agent is a bone density conservation agent. In another embodiment,
the compound is selected from the group consisting of
osteoprotegerin (OPG), BMP-2, BMP-4, vascular endothelial growth
factor (VEGF), alendronate, etidronate disodium, pamidronate,
risedronate, and tiludronate. In another embodiment, the compound
is osteoprotegerin (OPG), a naturally secreted decoy receptor that
inhibits osteoclast maturation and activity and induces osteoclast
apoptosis. In another embodiment, the active agent is a bone
restructuring element. Non-limiting examples of bone restructuring
elements are BMP peptides. Each possibility represents a separate
embodiment of the present invention.
[0147] In another embodiment, the compound is a bone morphogenetic
protein (BMP). In another embodiment, the compound is selected from
the group consisting of BMP-2 and BMP-4, which accelerate
osteoblast activity.
[0148] In another embodiment, the compound is vascular endothelial
growth factor (VEGF).
[0149] In another embodiment, the compound is an estrogen. In
another embodiment, the compound is selected from the group
consisting of bisphosphonate derivative. In another embodiment, the
bisphosphonate derivative is selected from the group consisting of
alendronate, etidronate disodium, pamidronate, risedronate, and
tiludronate.
[0150] Each compound represents a separate embodiment of the
present invention.
[0151] Anti-Fungal Agents
[0152] In another embodiment, the biologically active ingredient is
an antifungal drug, e.g. amphotericin B cholesteryl sulfate
complex, natamycin, amphotericin, clotrimazole, nystatin,
amphotericin B lipid complex, fluconazole, flucytosine,
griseofulvin, itraconazole, ketoconazole, benzoic acid and
salicylic acid, betamethasone and clotrimazole, butenafine,
carbol-fuchsin, ciclopirox, clioquinol, clioquinol and
hydrocortisone, clotrimazole, econazole, gentian violet,
haloprogin, iodoquinol and hydrocortisone, ketoconazole,
miconazole, naftifine, nystatin, nystatin and triamcinolone,
oxiconazole, sodium thiosulfate, sulconazole, terbinafine,
tolnaftate, triacetin, undecylenic acid and derivatives thereof,
butoconazole, clotrimazole, sulfanilamide, terconazole, and
tioconazole.
[0153] Targeting Moieties
[0154] In another embodiment, a matrix composition of methods and
compositions of the present invention further comprises a targeting
moiety capable of interacting with a target molecule. Preferably
the target molecule is selected from the group consisting of a
collagen molecule, a fibrin molecule and a heparin. In another
embodiment, the target molecule is another surface molecule that
forms part of the extracellular matrix (ECM) of a target cell. ECM
is produced and assembled locally by cells. The most important
cells involved in assembling and maintaining ECM are fibroblasts.
ECM contains polysaccharide chains called GAGs (glyosaminoglycans)
and various protein fibers e.g., collagen, elastin, fibronectin and
laminin.
[0155] In another embodiment, the targeting moiety is a fibronectin
peptide. Fibronectin is a high-molecular-weight glycoprotein that
binds ECM components such as collagen, fibrin and heparin. In
another embodiment, the targeting moiety is another targeting
moiety capable of interaction with a target molecule selected from
the group consisting of a collagen molecule, a fibrin molecule and
a heparin. Each possibility represents a separate embodiment of the
present invention.
[0156] "Fibronectin peptide" refers, in another embodiment, to a
full-length fibronectin protein. In another embodiment, the term
refers to a fragment of fibronectin. In another embodiment, the
fragment includes the collagen binding domain. Collagen binding
domains of fibronectin molecules are well known in the art, and are
described, for example, in Hynes, R O (1990). Fibronectins. New
York: Springer-Verlag and in Yamada, K M and Clark, R A F (1996).
Provisional matrix. In The Molecular and Cellular Biology of Wound
Repair (ed. R. A. F. Clark), pp. 51-93. New York: Plenum Press.
Each possibility represents a separate embodiment of the present
invention.
[0157] In another embodiment, the targeting moiety is incorporated
into the matrix composition. In another embodiment, the targeting
moiety is modified to confer ability to incorporate into the lipid
matrix. In another embodiment, the modification comprises binding
to a lipid moiety. A non-limiting example of a lipid moiety is
hydrogenated phosphatidylethanolamine (HPE). However, any lipid
moiety capable of incorporation into the lipid matrix is suitable.
In another embodiment, the targeting moiety is able to be
incorporated into the lipid matrix without modification. In another
embodiment, the targeting moiety is attached to the surface of a
matrix composition of the present invention. In another embodiment,
the targeting moiety is bound to the surface of the matrix
composition or vesicle by a hydrophobic anchor covalently bound to
the targeting moiety. In another embodiment, the targeting moiety
is bound to the lipid vesicles by a hydrophobic anchor. In another
embodiment, the targeting moiety is included during the preparation
of the matrix composition, allowing it to be located in deeper
layers, as well as on the surface of the matrix. Each possibility
represents a separate embodiment of the present invention.
[0158] In one embodiment, the target molecule is a collagen.
Collagens are well known in the art, and are described, for
example, in Khoshnoodi J et al (Molecular recognition in the
assembly of collagens: terminal noncollagenous domains are key
recognition modules in the formation of triple helical protomers. J
Biol. Chem. 281(50):38117-21, 2006). Each possibility represents a
separate embodiment of the present invention.
[0159] In one embodiment, the target molecule is a fibrin. Fibrins
are well known in the art, and are described, for example, in
Valenick L V et al (Fibronectin fragmentation promotes alpha4beta1
integrin-mediated contraction of a fibrin-fibronectin provisional
matrix. Exp Cell Res 309(1):48-55, 2005) and Mosesson M W
(Fibrinogen and fibrin structure and functions. J Thromb Haemost
3(8):1894-904, 2005). Each possibility represents a separate
embodiment of the present invention.
[0160] In one embodiment, the target molecule is a heparin.
Heparins are well known in the art, and are described, for example,
in Mosesson M W (Fibrinogen and fibrin structure and functions. J
Thromb Haemost 3(8):1894-904, 2005). Each possibility represents a
separate embodiment of the present invention.
[0161] Additional Components
[0162] In another embodiment, a matrix composition of methods and
compositions of the present invention further comprises a free
fatty acid. In another embodiment, the free fatty acid is an
omega-6 fatty acid. In another embodiment, the free fatty acid is
an omega-9 fatty acid. In another embodiment, the free fatty acid
is selected from the group consisting of omega-6 and omega-9 fatty
acids. In another embodiment, the free fatty acid has 14 or more
carbon atoms. In another embodiment, the free fatty acid has 16 or
more carbon atoms. In another embodiment, the free fatty acid has
16 carbon atoms. In another embodiment, the free fatty acid has 18
carbon atoms. In another embodiment, the free fatty acid has 16-22
carbon atoms. In another embodiment, the free fatty acid has 16-20
carbon atoms. In another embodiment, the free fatty acid has 16-18
carbon atoms. In another embodiment, the free fatty acid has 18-22
carbon atoms. In another embodiment, the free fatty acid has 18-20
carbon atoms. In another embodiment, the free fatty acid is
linoleic acid. In another embodiment, the free fatty acid is
linolenic acid. In another embodiment, the free fatty acid is oleic
acid. In another embodiment, the free fatty acid is selected from
the group consisting of linoleic acid, linolenic acid, and oleic
acid. In another embodiment, the free fatty acid is another
appropriate free fatty acid known in the art. In another
embodiment, the free fatty acid adds flexibility to the matrix
composition. In another embodiment, the free fatty acid slows the
in vivo release rate. In another embodiment, the free fatty acid
improves the consistency of the in vivo controlled release. In some
embodiments the fatty acid is unsaturated. In another embodiment,
the free fatty acid is saturated. In another embodiment,
incorporation of a saturated fatty acid having at least 14 carbon
atoms increases the gel-fluid transition temperature of the
resulting matrix composition.
[0163] In another embodiment, a free fatty acid is incorporated
into the matrix composition. Each type of fatty acid represents a
separate embodiment of the present invention.
[0164] In another embodiment, a matrix composition of methods and
compositions of the present invention further comprises a
tocopherol. The tocopherol of methods and compositions of the
present invention is, in another embodiment, E307
(.alpha.-tocopherol). In another embodiment, the tocopherol is
.beta.-tocopherol. In another embodiment, the tocopherol is E308
(.gamma.-tocopherol). In another embodiment, the tocopherol is E309
(.delta.-tocopherol). In another embodiment, the tocopherol is
selected from the group consisting of .alpha.-tocopherol,
.beta.-tocopherol, .gamma.-tocopherol, and .delta.-tocopherol. In
another embodiment, the tocopherol is incorporated into the matrix
composition. Each possibility represents a separate embodiment of
the present invention.
[0165] In another embodiment, a matrix composition of methods and
compositions of the present invention further comprises
physiologically acceptable buffer salts, which are well known in
the art. Non-limiting examples of physiologically acceptable buffer
salts are phosphate buffers. A typical example of a phosphate
buffer is 40 parts NaCl, 1 part KCl, 7 parts
Na.sub.2HPO.sub.4.2H.sub.2O and 1 part KH.sub.2PO.sub.4. In another
embodiment, the buffer salt is any other physiologically acceptable
buffer salt known in the art. Each possibility represents a
separate embodiment of the present invention.
[0166] Release Rates and General Characteristics of the Matrix
Compositions
[0167] The release characteristics from the matrix compositions are
designed to provide sustained release of the active agent or agents
from within the matrix to the desired site of action over a
prolonged period of time. The sustained release profile will
provide a therapeutically effective amount of the drug at least to
the local vicinity of the matrix composition for a period of days
or weeks or even months. While the compositions may have a minor
percentage of the active agent which is released immediately to
provide a therapeutic effect to the desired local site of action,
the majority of the material will be released over a prolonged
period of time. Typically up to 10-20% may be released immediately
from the matrix compositions. According to some embodiments the
release profile of the major portion of the agents achieves zero
order kinetics. According to some embodiments 40-70% of the active
agent is released under zero order kinetics. According to some
embodiments the release profile can be measured in vitro. According
to other embodiments the release profile may be measurable in vivo.
According to yet other embodiments the in vivo release will be
localized and will not be reflected in systemic drug levels.
[0168] The in vivo release time of 90% of the active ingredient for
matrix compositions of the present invention is preferably between
1 week and 6 months. In another embodiment, the release time is
between 4 days and 6 months. In another embodiment, the release
time is between 1 week and 5 months. In another embodiment, the
release time is between 1 week and 5 months. In another embodiment,
the release time is between 1 week and 4 months. In another
embodiment, the release time is between 1 week and 3 months. In
another embodiment, the release time is between 1 week and 2
months. In another embodiment, the release time is between 2 weeks
and 6 months. In another embodiment, the release time is between 2
weeks and 5 months. In another embodiment, the release time is
between 2 weeks and 4 months. In another embodiment, the release
time is between 2 weeks and 3 months. In another embodiment, the
release time is between 3 weeks and 6 months. In another
embodiment, the release time is between 3 weeks and 5 months. In
another embodiment, the release time is between 3 weeks and 4
months. In another embodiment, the release time is between 3 weeks
and 3 months. Each possibility represents a separate embodiment of
the present invention.
[0169] "Biodegradable" as used herein, refers to a substance
capable of being decomposed by natural biological processes at
physiological pH. "Physiological pH" refers to the pH of body
tissue, typically between 6-8. "Physiological pH" does not refer to
the highly acidic pH of gastric juices, which is typically between
1 and 3.
[0170] "Non-biodegradable" as used herein, refers to a substance
which is not degraded or eroded under normal mammalian
physiological conditions. Generally, a substance is considered
non-biodegradable if it is not degraded to a significant extent
(i.e., loses more than 5% of its mass and/or average polymer
length) by action of biological agents, and all during the average
time by which this substance will normally retain in the body
following its administration.
[0171] The weight ratio of total lipids to the polymer in order to
achieve lipid saturation can be determined by a number of methods,
as described herein. In another embodiment, the lipid:polymer
weight ratio of a composition of the present invention is between
1:1 and 9:1 inclusive. In another embodiment, the ratio is between
2:1 and 9:1 inclusive. In another embodiment, the ratio is between
3:1 and 9:1 inclusive. In another embodiment, the ratio is between
4:1 and 9:1 inclusive. In another embodiment, the ratio is between
5:1 and 9:1 inclusive. In another embodiment, the ratio is between
6:1 and 9:1 inclusive. In another embodiment, the ratio is between
7:1 and 9:1 inclusive. In another embodiment, the ratio is between
8:1 and 9:1 inclusive. In another embodiment, the ratio is between
1.5:1 and 9:1 inclusive. Each possibility represents a separate
embodiment of the present invention.
[0172] In another embodiment, the melting temperature (T.sub.m) of
the lipids in the matrix composition of the present invention is at
least 37.degree. C. In another embodiment, the T.sub.m is at least
40.degree. C. In another embodiment, the T.sub.m is at least
42.degree. C. In another embodiment, the T.sub.m is at least
44.degree. C. In another embodiment, the T.sub.m is at least
46.degree. C. In another embodiment, the T.sub.n, is at least
48.degree. C. In another embodiment, the T.sub.m is at least
50.degree. C. Each possibility represents a separate embodiment of
the present invention.
[0173] Implants and Other Pharmaceutical Compositions
[0174] In another embodiment, a matrix composition of the present
invention is in the form of an implant, following evaporation of
the organic solvents. The evaporation of the solvents is typically
done at temperatures ranging from 20 to 80.degree. C. According to
some embodiments, the evaporation of the solvents can be done at
temperatures ranging from 20 to 60.degree. C.
[0175] In another embodiment, the implant is homogeneous. In
another embodiment, the implant is manufactured by a process
comprising the step of freeze-drying the material in a mold. Each
possibility represents a separate embodiment of the present
invention.
[0176] In another embodiment, the present invention provides an
implant comprising an antibiotic-containing matrix composition of
the present invention. In another embodiment, the present invention
provides an implant comprising an NSAID-containing matrix
composition of the present invention. In another embodiment, the
present invention provides an implant comprising a bone resorption
inhibitor-containing matrix composition of the present invention.
In another embodiment, the present invention provides an implant
comprising a matrix composition of the present invention that
contains an antibiotic and an NSAID. In another embodiment, the
present invention provides an implant comprising a matrix
composition of the present invention that contains an antibiotic
and a bone resorption inhibitor. In another embodiment, the present
invention provides an implant comprising a matrix composition of
the present invention that contains a bone resorption inhibitor and
an NSAID. In another embodiment, the present invention provides an
implant comprising a matrix composition of the present invention
that contains an antibiotic, an NSAID, and a bone resorption
inhibitor. Each possibility represents a separate embodiment of the
present invention.
[0177] In another embodiment, the process of creating an implant
from a composition of the present invention comprises the steps of
(a) creating a matrix composition according to a method of the
present invention in the form of a bulk material; (b) transferring
the bulk material into a mold or solid receptacle of a desired
shaped; (c) freezing the bulk material; and (d) lyophilizing the
bulk material.
[0178] In another embodiment, the present invention provides a
pharmaceutical composition comprising a matrix composition of the
present invention and a pharmaceutically acceptable excipient.
[0179] In another embodiment, a matrix composition of the present
invention is in the form of microspheres, following evaporation of
the organic solvents. In another embodiment, the microspheres are
homogeneous. In another embodiment, the microspheres are
manufactured by a process comprising the step of spray-drying. Each
possibility represents a separate embodiment of the present
invention.
[0180] In another embodiment, the present invention provides
microspheres made of a matrix composition of the present invention.
In another embodiment, the present invention provides a
pharmaceutical composition comprising microspheres of the present
invention and a pharmaceutically acceptable excipient. In another
embodiment, the pharmaceutical composition is in a parenterally
injectable form. In another embodiment, the pharmaceutical
composition is in an infusible form. In another embodiment, the
excipient is compatible for injection. In another embodiment, the
excipient is compatible for infusion. Each possibility represents a
separate embodiment of the present invention.
[0181] In another embodiment, the particle size of microspheres of
the present invention is approximately 500-2000 nm. In another
embodiment, the particle size is about 400-2500 nm. In another
embodiment, the particle size is about 600-1900 nm. In another
embodiment, the particle size is about 700-1800 nm. In another
embodiment, the particle size is about 500-1800 nm. In another
embodiment, the particle size is about 500-1600 nm. In another
embodiment, the particle size is about 600-2000 nm. In another
embodiment, the particle size is about 700-2000 nm. In another
embodiment, the particles are of any other size suitable for
pharmaceutical administration. Each possibility represents a
separate embodiment of the present invention.
[0182] Therapeutic Methods
[0183] In another embodiment, the present invention provides a
method of administering an antibiotic to a subject in need thereof,
the method comprising the step of administering to the subject a
matrix composition of the present invention, thereby administering
an antibiotic to a subject in need thereof. In another embodiment,
a pharmaceutical composition comprising the matrix composition is
administered. In another embodiment, an implant comprising the
matrix composition is administered. In another embodiment, an
injectable formulation comprising the matrix composition is
injected. Each possibility represents a separate embodiment of the
present invention.
[0184] In another embodiment, the present invention provides a
method of administering a non-steroidal anti-inflammatory drug
(NSAID) to a subject in need thereof, the method comprising the
step of administering to the subject a matrix composition of the
present invention, thereby administering an NSAID to a subject in
need thereof. In another embodiment, a pharmaceutical composition
comprising the matrix composition is administered. In another
embodiment, an implant comprising the matrix composition is
administered. In another embodiment, an injectable formulation
comprising the matrix composition is injected. Each possibility
represents a separate embodiment of the present invention.
[0185] In another embodiment, the present invention provides a
pharmaceutical composition for administering an antibiotic to a
subject in need thereof, comprising a matrix composition of the
present invention. In another embodiment, the pharmaceutical
composition is an implant. In another embodiment, the
pharmaceutical composition is an injectable composition. Each
possibility represents a separate embodiment of the present
invention.
[0186] In another embodiment, the present invention provides a
pharmaceutical composition for administering an NSAID to a subject
in need thereof, comprising a matrix composition of the present
invention. In another embodiment, the pharmaceutical composition is
an implant. In another embodiment, the pharmaceutical composition
is an injectable composition. Each possibility represents a
separate embodiment of the present invention.
[0187] In another embodiment, the present invention provides a
pharmaceutical composition for co-administering an antibiotic and
an NSAID to a subject in need thereof, comprising a matrix
composition of the present invention. In another embodiment, the
pharmaceutical composition is an implant. In another embodiment,
the pharmaceutical composition is an injectable composition. Each
possibility represents a separate embodiment of the present
invention.
[0188] In another embodiment, the present invention provides a
method of treating periodontitis in a subject in need thereof, said
method comprising the step of administering to said subject a
matrix composition of the present invention, thereby treating
periodontitis. "Periodontitis" refers to an inflammatory disease
affecting the tissues that surround and support the teeth. In
another embodiment, periodontitis involves progressive loss of the
alveolar bone around the teeth and may eventually lead to the
loosening and subsequent loss of teeth if left untreated.
Periodontitis in some cases has a bacterial etiology. In another
embodiment, the periodontitis is a chronic periodontitis. In
another embodiment, the periodontitis is any other type of
periodontitis known in the art. Each possibility represents a
separate embodiment of the present invention.
[0189] In another embodiment, the present invention provides a
method of stimulating bone augmentation in a subject in need
thereof, said method comprising the step of administering to said
subject a matrix composition of the present invention, thereby
stimulating bone augmentation. In another embodiment, the subject
has a disease or disorder selected from the group consisting of
osteosarcoma/malignant fibrous histiocytoma of bone (PDQ),
osteosarcoma, chondrosarcoma, Ewing's sarcoma, malignant fibrous
histiocytoma, fibrosarcoma and malignant fibrous histiocytoma,
giant cell tumor of bone, chordoma, lymphoma, multiple myeloma,
osteoarthritis, Paget's disease of bone, arthritis, degenerative
changes, osteoporosis, osteogenesis imperfecta, bone spurs, renal
osteodystrophy, hyperparathyroidism, osteomyelitis, enchondroma,
osteochondroma, osteopetrosis, and a diabetes-associated bone or
joint disorder. In another embodiment, the matrix composition is in
the form of an implant. Each possibility represents a separate
embodiment of the present invention.
[0190] In another embodiment, the present invention provides a
method of reducing an incidence of complications from orthopedic
surgery in a subject in need thereof, said method comprising the
step of administering to said subject a matrix composition of the
present invention, thereby reducing an incidence of complications
from orthopedic surgery. In another embodiment, the orthopedic
surgery is selected from the group consisting of hand surgery,
shoulder and elbow surgery, total joint reconstruction
(arthroplasty), pediatric orthopedics, foot and ankle surgery,
spine surgery, knee arthroscopy, knee meniscectomy, shoulder
arthroscopy, shoulder decompression, carpal tunnel release, knee
chondroplasty, removal of a support implant, knee anterior cruciate
ligament reconstruction, knee replacement, repair of femoral neck
fracture, repair of trochanteric fracture, debridement of skin,
muscle, or bone fracture, repair of knee menisci, hip replacement,
shoulder arthroscopy/distal clavicle excision, repair of rotator
cuff tendon, repair fracture of radius (bone)/ulna, laminectomy,
repair of ankle fracture (bimalleolar type), shoulder arthroscopy
and debridement, lumbar spinal fusion, repair fracture of the
distal part of radius, low back intervertebral disc surgery, incise
finger tendon sheath, repair of ankle fracture (fibula), repair of
femoral shaft fracture, and repair of trochanteric fracture. In
another embodiment, the matrix composition is in the form of an
implant. In another embodiment, the implant is administered during
the orthopedic surgery. Each possibility represents a separate
embodiment of the present invention.
[0191] In another embodiment, the present invention provides a
method of enhancing an effectiveness of surgical regenerative
procedure in a subject in need thereof, said method comprising the
step of administering to said subject a matrix composition of the
present invention, thereby enhancing an effectiveness of surgical
regenerative procedure. In another embodiment, the surgical
regenerative procedure is a periodontal procedure. In another
embodiment, the surgical regenerative procedure comprises
administering an implant (an implantology procedure). In another
embodiment, the implantology procedure is directed to ridge or
sinus augmentation. In another embodiment, the matrix composition
is in the form of an implant. In another embodiment, the implant is
administered during the surgical procedure. Each possibility
represents a separate embodiment of the present invention.
[0192] In another embodiment, the present invention provides a
method of treating an osteomyelitis in a subject in need thereof,
said method comprising the step of administering to said subject a
matrix composition of the present invention, thereby treating an
osteomyelitis. In another embodiment, the matrix composition is in
the form of an implant. In another embodiment, the implant is
administered at or near the site of osteomyelitis. Each possibility
represents a separate embodiment of the present invention.
[0193] In another embodiment, a matrix composition of the present
invention is administered for aiding orthopedic bone and soft
tissue recovery. The compounds are administered during or after a
procedure selected from the group consisting of knee arthroscopy
and meniscectomy, shoulder arthroscopy and decompression, carpal
tunnel release, knee arthroscopy and chondroplasty, removal of
support implant, knee arthroscopy and anterior cruciate ligament
reconstruction, knee replacement, repair of femoral neck fracture,
repair of trochanteric fracture, debridement of
skin/muscle/bone/fracture, knee arthroscopy repair of both menisci,
hip replacement, shoulder arthroscopy/distal clavicle excision,
repair of rotator cuff tendon, repair fracture of radius
(bone)/ulna, laminectomy, repair of ankle fracture (bimalleolar
type), shoulder arthroscopy and debridement, lumbar spinal fusion,
repair fracture of the distal part of radius, low back
intervertebral disc surgery, incise finger tendon sheath, repair of
ankle fracture (fibula), repair of femoral shaft fracture, and
repair of trochanteric fracture.
[0194] In another embodiment, a matrix composition of the present
invention is administered for homeostasis, reducing infections and
avoiding tissue adhesions by the use of products such as sponges
and membranes.
[0195] In another embodiment, a matrix composition of the present
invention is administered for reducing of inflammatory reaction
around suture materials.
[0196] In another embodiment, a matrix composition of the present
invention is administered for sustained release of pharmaceuticals
in the respiratory system: the lower respiratory tract such as the
lungs, bronchi and alveoli and the upper respiratory tract such as
the nose, nasal cavity, ethmoidal air cells, frontal sinuses,
maxillary sinus, larynx and trachea. The administration of
pharmaceuticals for treatment of systemic diseases or specific
respiratory diseases such as obstructive conditions, restrictive
conditions, vascular diseases, environmental, and infectious, for
example, treatment of sinusitis.
[0197] In another embodiment, a matrix composition of the present
invention is administered for sustained release of pharmaceuticals
in the gastrointestinal tract for systemic treatment and specific
gastro intestinal tract diseases.
[0198] Methods of Making Matrix Compositions
[0199] In order to obtain the compositions of the invention any
suitable method may be employed that will yield a homogeneous
dispersion of the polymer and the lipids in a water resistant
matrix. Advantageously according to some embodiments the methods
employed avoid the use of water at any stage of the manufacturing
process.
[0200] According to some embodiments the polymer is mixed
separately with appropriate selected volatile organic solvent(s) on
the one hand and the phospholipids together with the active
pharmaceutical agent are mixed with its appropriate selected
solvent(s) or solvents prior to mixing together with the
polymer.
[0201] In certain embodiments, the present invention provides a
method of producing a matrix composition, the method comprising the
steps of:
[0202] (a) mixing into a first volatile organic solvent: (i) a
non-biodegradable polymer and (ii) sterol; and
[0203] (b) mixing separately into a second volatile organic
solvent: (i) an active agent; (ii) a phosphatidylcholine and
optionally (iii) a phosphatidylethanolamine; and
[0204] (c) mixing and homogenizing the products resulting from
steps (a) and (b).
[0205] In another embodiment, phosphatidylethanolamine is included
in the volatile organic solvent of step (a) instead of or in
addition to a phosphatidylethanolamine added to the volatile
organic solvent of step (b). In another embodiment, the
biocompatible polymer is selected from the group consisting of
non-biodegradable polymer, a biodegradable polymer other than
polyester and any combination thereof. In some embodiments the
first volatile organic solvent is a non-polar solvent. In some
embodiments the second volatile organic solvent is a water miscible
solvent. In cases where the active agent is a protein or peptide it
is important to select solvents that will not denature or impair
the activity of the protein. In particular embodiments the active
agent is selected from the group consisting of an NSAID, an
antibiotic, an antifungal agent, a steroid, an anticancer agent, an
osteogenic factor and a bone resorption inhibitor and mixtures
thereof.
[0206] In another embodiment, the mixture of step (a) containing a
volatile organic solvent is homogenized prior to mixing it with the
solution of step (b). In another embodiment, the volatile organic
solvent or mixture of volatile organic solvents used in step (a)
may be same or different than the volatile organic solvent or
mixture of organic solvents used in step (b). In another
embodiment, the mixture of step (b) is homogenized prior to mixing
it with the mixture of step (a). In another embodiment, the polymer
in the mixture of step (a) is lipid saturated. In another
embodiment, the matrix composition is lipid saturated. Preferably,
the polymer and the phosphatidylcholine are incorporated into the
matrix composition. In another embodiment, the active agent as well
is incorporated into the matrix composition. In another embodiment,
the matrix composition is in the form of a lipid-saturated matrix
whose shape and boundaries are determined by the polymer. Each
possibility represents a separate embodiment of the present
invention.
[0207] In another embodiment, the phosphatidylethanolamine of
methods and compositions of the present invention has saturated
fatty acid moieties. In another embodiment, the fatty acid moieties
have at least 14 carbon atoms. In another embodiment, the fatty
acid moieties have 14-20 carbon atoms. Each possibility represents
a separate embodiment of the present invention.
[0208] In another embodiment, the phosphatidylcholine of methods
and compositions of the present invention has saturated fatty acid
moieties. In another embodiment, the fatty acid moieties have at
least 14 carbon atoms. In another embodiment, the fatty acid
moieties have at least 16 carbon atoms. In another embodiment, the
fatty acid moieties have 14-18 carbon atoms. In another embodiment,
the fatty acid moieties have 16-20 carbon atoms. Each possibility
represents a separate embodiment of the present invention.
[0209] In another embodiment, the weight ratio of total lipids to
polymer in the first volatile organic solvent is such that the
polymer in this mixture is lipid-saturated. In another embodiment
for purposes of illustration, in the case wherein the polymer is
predominantly 8 KDa PEG, the molar ratio of total lipids to 8 KDa
PEG is typically in the range of 10-50 inclusive. In another
embodiment, the molar ratio of total lipids to 8 KDa
[0210] PEG is between 10-100 inclusive. In another embodiment, the
molar ratio is between 20-200 inclusive. In another embodiment, the
molar ratio is between 20-300 inclusive. In another embodiment, the
molar ratio is between 30-400 inclusive. Each possibility
represents a separate embodiment of the present invention.
[0211] This is important since the elimination of non-biodegradable
polymer fragment by the kidney is limited to small fragments. In
the case of PEG it is limited to chains of 5000 Dalton, and
preferably up to 2000 Dalton is used. Using large polymeric chins
can elevate the inner strength of the matrix, were as the
resistency of the specific linker can influence the degradation
rate, reflecting on the release rate of the drug.
[0212] Each of the components of the above method and other methods
of the present invention is defined in the same manner as the
corresponding component of the matrix compositions of the present
invention.
[0213] In another embodiment, step (a) of the production method
further comprises adding to the volatile organic solvent a
phosphatidylethanolamine. In another embodiment, the
phosphatidylethanolamine is the same phosphatidylethanolamine
included in step (b). In another embodiment, the
phosphatidylethanolamine is a different phosphatidylethanolamine
that may be any other phosphatidylethanolamine known in the art. In
another embodiment, the phosphatidylethanolamine is selected from
the group consisting of the phosphatidylethanolamine of step (b)
and a different phosphatidylethanolamine. Each possibility
represents a separate embodiment of the present invention.
[0214] In another embodiment, step (a) of the production method
further comprises adding to the volatile organic solvent a
tocopherol.
[0215] In another embodiment, step (b) of the production method
further comprises adding to the volatile organic solvent
physiologically acceptable buffer salts. Non-limiting examples of
physiologically acceptable buffer salts are phosphate buffers. A
typical example of a phosphate buffer is 40 parts NaCl, 1 part KCl,
7 parts Na.sub.2HPO.sub.4.2H.sub.2O and 1 part KH.sub.2PO.sub.4. In
another embodiment, the buffer salt is any other physiologically
acceptable buffer salt known in the art. Each possibility
represents a separate embodiment of the present invention.
[0216] In another embodiment, step (b) of the production method
further comprises adding to the volatile organic solvent a
phospholipid selected from the group consisting of a
phosphatidylserine, a phosphatidylglycerol, a sphingomyelin, and a
phosphatidylinositol.
[0217] In another embodiment, step (b) of the production method
further comprises adding to the volatile organic solvent a
sphingolipid. In another embodiment, the sphingolipid is ceramide.
In another embodiment, the sphingolipid is a sphingomyelin. In
another embodiment, the sphingolipid is any other sphingolipid
known in the art. Each possibility represents a separate embodiment
of the present invention.
[0218] In another embodiment, step (b) of the production method
further comprises adding to the water-miscible, volatile organic
solvent an omega-6 or omega-9 free fatty acid. In another
embodiment, the free fatty acid has 16 or more carbon atoms. Each
possibility represents a separate embodiment of the present
invention.
[0219] In another embodiment, each step of the production method is
substantially free of aqueous solution. In another embodiment, each
step is substantially free of the presence of water or any aqueous
solution. As provided herein, producing matrix compositions of the
present invention in a water-free process enables lipid saturation.
In another embodiment, each step of the production method may
involve the presence of water in an amount not greater than 20% of
the total liquid volume (water and organic solvents). The aqueous
solution or water will be eliminated through evaporation together
with the organic solvents as described below.
[0220] Upon mixing, a homogenous mixture is formed, since the
polymer is lipid-saturated in the mixture of step (a). In another
embodiment, the homogenous mixture takes the form of a homogenous
liquid. In another embodiment, upon freeze-drying or spray-drying
the mixture, vesicles are formed. Each possibility represents a
separate embodiment of the present invention.
[0221] In another embodiment, the production method further
comprises the step of evaporating the solvent present in the
product of step (c). In another embodiment, the evaporation
utilizes atomization of the mixture. In another embodiment, the
mixture is atomized into dry, heated air. Typically, atomization
into heated air evaporates all water immediately, obviating the
need for a subsequent drying step. In another embodiment, the
mixture is atomized into a water-free solvent. In another
embodiment, the evaporation is performed by spray drying. In
another embodiment, the evaporation is performed by freeze drying.
In another embodiment, the evaporation is performed using liquid
nitrogen. In another embodiment, the evaporation is performed using
liquid nitrogen that has been pre-mixed with ethanol. In another
embodiment, the evaporation is performed using another suitable
technique known in the art. Each possibility represents a separate
embodiment of the present invention.
[0222] In another embodiment, a method of the present invention
further comprises the step of vacuum-drying the composition. In
another embodiment, the step of vacuum-drying is performed
following the step of evaporating. Each possibility represents a
separate embodiment of the present invention.
[0223] In another embodiment, the method of the present invention
further comprises the step of evaporating the organic volatile
solvent by heating the product of step (c). The heating is
continuing until the solvent is eliminated and in a typical
temperature between room temperature to 80.degree. C. In another
embodiment a step of vacuum-drying is performed following the step
of solvent evaporation. Each possibility represents a separate
embodiment of the present invention.
[0224] Lipid Saturation and Techniques for Determining Same
[0225] "Lipid saturated," as used herein, refers to saturation of
the polymer of the matrix composition with phospholipids in
combination with any hydrophobic drug and targeting moiety present
in the matrix, and any other lipids that may be present. As
described herein, matrix compositions of the present invention
comprise, in some embodiments, phospholipids other than
phosphatidylcholine. In other embodiments, the matrix compositions
comprise lipids other than phospholipids. The matrix composition is
saturated by whatever lipids are present. "Saturation" refers to a
state wherein the matrix contains the maximum amount of lipids of
the type utilized that can be incorporated into the matrix. Methods
for determining the polymer:lipid ratio to attain lipid saturation
and methods of determining the degree of lipid saturation of a
matrix are described herein. Each possibility represents a separate
embodiment of the present invention.
[0226] In another embodiment, the matrix composition of methods and
compositions of the present invention is substantially free of
water. "Substantially free of water" refers, in another embodiment,
to a composition containing less than 1% water by weight. In
another embodiment, the term refers to a composition containing
less than 0.8% water by weight. In another embodiment, the term
refers to a composition containing less than 0.6% water by weight.
In another embodiment, the term refers to a composition containing
less than 0.4% water by weight. In another embodiment, the term
refers to a composition containing less than 0.2% water by weight.
In another embodiment, the term refers to the absence of amounts of
water that affect the water-resistant properties of the
composition. In another embodiment, the term refers to a
composition manufactured without the use of any aqueous solvents.
In another embodiment, producing the composition using a process
substantially free of water, as described herein, enables lipid
saturation. Lipid saturation confers upon the matrix composition
ability to resist bulk degradation in vivo; thus, the matrix
composition exhibits the ability to mediate extended release on a
scale of several weeks or months. Each possibility represents a
separate embodiment of the present invention.
[0227] In another embodiment, the matrix composition is essentially
free of water. "Essentially free" refers to a composition
comprising less than 0.1% water by weight. In another embodiment,
the term refers to a composition comprising less than 0.08% water
by weight. In another embodiment, the term refers to a composition
comprising less than 0.06% water by weight. In another embodiment,
the term refers to a composition comprising less than 0.04% water
by weight. In another embodiment, the term refers to a composition
comprising less than 0.02% water by weight. In another embodiment,
the term refers to a composition comprising less than 0.01% water
by weight. Each possibility represents a separate embodiment of the
present invention.
[0228] In another embodiment, the matrix composition is free of
water. In another embodiment, the term refers to a composition not
containing detectable amounts of water. Each possibility represents
a separate embodiment of the present invention.
[0229] In another embodiment, the matrix composition is dry. "Dry"
refers, in another embodiment, to the absence of detectable amounts
of water or organic solvent.
[0230] In another embodiment, the water permeability of the matrix
composition has been minimized. "Minimizing" the water permeability
refers to a process of producing the matrix composition in organic
solvents, as described herein, in the presence of an amount of
lipid that has been determined to minimize the permeability to
penetration of added water. The amount of lipid required can be
determined by hydrating the vesicles with a solution containing
tritium-tagged water, as described herein.
[0231] In another embodiment, "lipid saturation" refers to filling
of internal gaps (free volume) within the lipid matrix as defined
by the external border of the polymeric backbone. The gaps are
filled with the phospholipids in combination with other type of
lipids, hydrophobic drug and targeting moiety present in the
matrix, to the extent that additional lipid moieties can no longer
be incorporated into the matrix to an appreciable extent.
[0232] In one embodiment, the following method is used to determine
the degree of lipid saturation:
[0233] Following manufacture, vesicles are hydrated and isolated by
centrifugation or filtration. Lipids that not entrapped in the
vesicles form free micelles or liposomes and are located in the
supernatant. The overall lipid contents of the supernatant and the
vesicles are quantified. In this manner, the entrapped vs. free
lipid contents are determined for various formulation containing
different lipid:polymer ratios at the outset. Thus, the actual,
experimental, maximum lipid/polymer ratio is determined.
[0234] In another embodiment, the following method is used to
determine the degree of lipid saturation:
[0235] Following manufacture, vesicles are hydrated with a solution
containing tritium-tagged water, washed with tritium-free solution,
and isolated by centrifugation or filtration, and the amount of
water entrapped per polymer mass is quantified. This is repeated
with different lipid:polymer ratios, in order to determine the
amount of lipids required to saturate the free volume in the
polymeric vesicles.
[0236] "Zero-order release rate" or "zero order release kinetics"
means a constant, linear, continuous, sustained and controlled
release rate of the pharmaceutical active agent from the polymer
matrix, i.e. the plot of amounts of pharmaceutical active agent
released vs. time is linear.
EXPERIMENTAL DETAILS SECTION
Example 1
Platform Technology for Production of Drug Carrier Compositions
Overview
[0237] To produce lipid-saturated polymer matrices, two mixtures
are created.
1. A non-biodegradable polymer and a sterol and/or phospholipid
component are mixed with a volatile organic solvent, which is mixed
to yield a solution or suspension of lipid-saturated polymer
matrix, as measured by its differential scanning calorimetric (DSC)
profile. 2. The active agent and a phospholipid component are mixed
with a second volatile organic solvent to yield a second solution
or suspension. 3. The two solutions or suspensions are combined and
mixed until equilibrium is reached; the organic solvents are then
evaporated, yielding a drug-containing, lipid-saturated polymer
matrix. Exemplary protocol
I. Preparation of First Solution
Stock Solutions:
[0238] Stock solution 1 (SS1): PEG 8000, 300 mg/ml in ethyl
acetate. Stock solution 2 (SS2): Cholesterol (CH), 30 mg/ml in
ethyl acetate. Stock solution 3 (SS3): Doxycycline-Hyclate
(Doxy-H), 50 mg/ml in Methanol:ethyl acetate (1:1 v/v).
[0239] Solution A1: 0.2 volume of SS1 was mixed with 1 volume of
SS2 (PLGA 50 mg/ml, CH 25 mg/ml).
[0240] Solution A2: 0.2 volume of SS1 was mixed with 1 volume of
ethyl acetate (PLGA 50 mg/ml).
[0241] The mixture is mixed. The entire process is performed at
room temperature. A fat-polymer matrix is thus obtained.
II. Preparation of Second Solution
[0242] Solution B1: 1,2-distearoyl-sn-glycero-3-phosphocholine
(DSPC; final concentration 225 mg/ml) dissolved in 0.75 ml SS3 was
mixed with 0.25 ml ethyl acetate (final Doxy-H concentration 37.5
mg/ml).
[0243] Solution B2: 1,2-dimyristoyl-sn-glycero-3-phosphocholine
(DMPC; final concentration 225 mg/ml) dissolved in 0.75 ml SS3 was
mixed with 0.25 ml ethyl acetate (final Doxy-H concentration 37.5
mg/ml).
[0244] Solution B3: 1,2-dipalmitoyl-sn-glycero-3-phosphocholine
(DPPC; final concentration 225 mg/ml) dissolved in 0.75 ml SS3 was
mixed with 0.25 ml ethyl acetate (final Doxy-H concentration 37.5
mg/ml).
[0245] Solution B4: 0.75 ml SS3 with 0.25 ml ethyl acetate (final
Doxy-H concentration 37.5 mg/ml).
[0246] The mixture is mixed, homogenized or sonicated. In some
cases, prior to mixing, homogenization or sonication, a non-polar,
volatile organic solvent, e.g. ethyl acetate, is included with the
mixture, which is stirred gently for 30 minutes. Typically the
entire process is conducted at room temperature, but higher
temperatures of up to 80.degree. C. are used, typically when highly
saturated lipids are used.
[0247] No water is required in the mixture.
III--Mixing the Polymer with the Drug/Protein Mixture
[0248] The second suspension (or solution) is added to the first
solution under stirring. Stirring is continued for up to 5 h. The
entire process is performed at room temperature and up to
60.degree. C., all according to the specific formulation, the
nature of the lipids in use and the specific drug. Alternatively,
first and second solution may be vigorously mixed using a vortex
followed by incubation at 45.degree. C. for 5 minutes. The
resulting mixture should be homogenous.
[0249] Solution AB: 1 volume of solution B1, B2, B3 or B4 was mixed
with 1.5 volumes of solution A1. Alternatively, 1 volume of
solution B4 was mixed with 1.5 volume of solution A2.
IV--Evaporation of the Solvents
[0250] In some experiments, the solution from stage III is atomized
into dry, heated air.
[0251] In other experiments, the solution from stage III is
atomized into ethanol covered by liquid nitrogen or only liquid
nitrogen without ethanol, after which the nitrogen and/or ethanol
(as above) are evaporated.
[0252] In other experiments, when coating of surfaces is performed;
the suspension from stage III is mixed with the particles (e.g.
tricalcium phosphate) or devices to be coated followed by
evaporation of the volatile organic solvents. The entire process is
performed at a temperature of 40-60.degree. C., preferably,
solvents are evaporated by incubation at a temperature of about
45.degree. C. for about an hour or until no liquid is visualized
followed by overnight vacuum.
V--Vacuum Drying
[0253] Coated particles and coated devices are vacuum-dried for
storage.
Example 2
Preparation of Doxycycline Hyclate--Bone Particles Filler
Formulation for Treatment of Bone Infection Using PEG and DPPC
I. Preparation of First Solution/Suspension
[0254] The following materials are mixed into Chloroform:
i. Poly ethylene glycol (PEG) 8000 ii Cholesterol-50% w/w vs.
PEG.
[0255] The mixture is mixed until a clear solution is obtained. The
entire process is performed at room temperature. A lipid-polymer
combination matrix is thus obtained.
II. Preparation of Second Solution/Suspension
[0256] The following materials are mixed with a volatile organic
solvent (methanol and ethyl acetate):
i Active compound--an antibiotic Doxycycline hyclate (DOX) ii A
phosphatidylcholine--DPPC (16:0) present as 300% w/w vs. PEG.
[0257] The mixture is thoroughly mixed. The entire process is
conducted at room temperature.
[0258] No water is required in the mixture.
III--Mixing the First and the Second Solution
[0259] The second solution is added to the first solution while
stirring. (Ratio of 3:2 v:v) Stirring is continued for one minute.
The entire process is performed at a room temperature.
IV--Evaporation Following Surface Coating
[0260] In order to coat bone filler particles, the particles were
added to the mixture of stage III followed by evaporation of the
volatile organic solvents. The entire process was performed at a
temperature of 45.degree. C.
[0261] The ratio between the volume of the mixture of stage III and
the mass of the bone particles will determine the release period of
the drug post hydration of the coated particles.
V--Vacuum Drying
[0262] Coated bone particles are vacuum-dried for storage.
Example 3
Validation of the Intactness of the Ingredients of the Matrix
Composition
[0263] The matrix composition ingredients (PEG, cholesterol,
phospholipids and Doxy-H) were extracted by adding 0.2 ml of DCM to
the dry matrix composition.
[0264] 10 .mu.L from the extract were injected onto an HPLC so as
to verify the Doxy-H intactness and concentration.
[0265] 5 .mu.L of the extract were loaded on TLC sheets and run
using different mobiles in order to determine the cholesterol and
phospholipids stability (The mobile phase for cholesterol was:
Hexan/Ether/Acetic acid, 70/30/1 (v/v/v); the mobile phase for the
Phospholipids was: Chloroform/MeOH/water 65/35/4 (v/v/v)).
Results:
[0266] The Doxy-H extracted from the complex gave a single peak at
10.37 min identical to the peak of Doxy-H standard. The major peak
was more than 99% pure. The cholesterol and the phospholipids gave
single spot when ran on the TLC sheet, indicating that no derivates
were formed during the preparation of the complex with a Rf of 0.26
for cholesterol and 0.58 for phospholipids (FIGS. 1A and B).
Example 4
Release Profile of Doxy-H from the TCP-Matrix Composition
[0267] In order to determine the release profile of the drug
(Doxy-H) from the matrix composition, the matrix composition 100 mg
was hydrated with 1 ml of 5% FBS in DDW.
[0268] An hour after hydration the solution was collected and the
concentration of Doxy-H in the solution was determined by HPLC.
This procedure was repeated daily for 20 days.
[0269] During the first 6 days the concentration of Doxy-H in the
sample was determined before and after spin-down (6000 rpm for 2
min) to evaluate the amount of encapsulated Doxy-H.
Results:
[0270] (i) During the first hour 21, 24 and 30% of the trapped
Doxy-H was released from PEG+CH+Doxy+DSPC matrix composition,
PEG+CH+Doxy+DMPC matric composition and PEG+CH+Doxy matrix
composition, respectively. It is to be emphasized that the drug
detected in the hydration solution contained free drug molecules as
well as drug molecules attached to small particles (micrometer in
size) of the matrix. In order to determine the amount of drug
released from the matrix versus drug molecules which are bound to
matrix particles, the hydration solution collected was centrifuged
at 6,000 RPM for 2 min, and the concentration of the drug in the
solution was determined. It was found that for matrix compositions
comprising phospholipids only about 50% of the drug was found in
solution whereas about 50% was found in the pellet formed during
spin-down (indicating the drug is attached to the matrix), while in
the matrix composition without phospholipids (PEG+CH+Doxy Polypid
Complex) less than 30% of drug was found in solution, whereas more
than 70% was found in the pellet. [0271] (ii) During the first 6
days, the amount of free Doxy-H released from matrix compositions
comprising phospholipids (either DMPC or DSPC) was found to be the
same. Yet, the total amount of drug released (free drug and drug
attached to micrometer particles of the matrix) was higher in the
DMPC complexes. This difference is in correlation with the lower
melting point of DMPC; enhancing its dissociation from the matrix.
[0272] (iii) The release of Doxy-H from matrix formulations
comprising phospholipids displayed a zero order kinetics starting
at day 3 (FIG. 2), while the release of Doxy-H from the polymeric
complex was logarithmic in nature (data not shown).
Example 5
Visualizing the Released Particles from the Matrix Composition
[0273] In order to determine the structure of the particles
released upon hydration of the matrix composition, we have hydrated
two matrix compositions (PEG+CH+DPPC+Doxy-H and PEG+Doxy-H) for 24
hours after which the supernatant was collected and looked at using
a light microscope connected to a Ueye digital camera. Liposomal
structures having an average size of 50 .mu.m, mostly multi-lamelar
vesicles (MLV) were detected in the supernatant of the matrix
comprising PEG+CH+DPPC+Doxy-H (FIG. 3B), whereas polymeric
structures having an average size of .about.5 .mu.m were detected
in the supernatant of the matrix comprising PEG+Doxy-H (FIG.
3A).
Example 6
The Stability of Doxy-H in the Matrix Composition
[0274] A matrix composition PEG-CH-Doxy-H-DMPC was hydrated for 15
days. The supernatant was then removed and Doxy-H was extracted
from the complex with acetonitrile: 0.01N HCl. The stability of the
extracted Doxy-H was determined by HPLC.
[0275] The extracted Doxy-H was intact and no derivates were
formed. The main Doxy-H peak was .about.98% pure. The total amount
of Doxy-H extracted was 70.44 .mu.g. Within the first 15 days the
hydrated complex released 883.579 .mu.g. the total amount of Doxy-H
released was 954 .mu.g. This amount is .about.90% of the total
amount of the encapsulated Doxy-H in the formula.
Example 7
DSC Profiles of the Peg/Cholesterol/Doxy-H/DPPC Matrix
Composition
[0276] The basic principle underlying the differential scanning
calorimetry (DSC) technique is that, when a sample undergoes a
physical transformation such as, for example, an interaction with
another sample, more or less heat will need to flow to it than to
the reference to maintain the temperature of the interacting
samples the same as the temperature of the samples alone. Without
wishing to be bound by theory or mechanism of action, this may
imply, for example, that the reagent associated or assembled with
the polymer alters the phase transition characteristics of the
polymer, which may further imply that the reagent associated with
the polymer interferes with the self assembly of the polymeric
chains.
[0277] The nature of the interaction between the different
components of the matrix composition according to certain
embodiments of the invention was analyzed using DSC; 75 .mu.L of
either the stock solutions of the components alone as well as
combinations thereof, were put into a DSC sample holder. The
solvent was evaporated by incubating the holder on a dry block set
to 45.degree. C. for 30 min followed by 30 min under vacuum. DSC
curves were then recorded at a scan rate of 5.degree. C./min.
Results:
[0278] i) PEG:cholesterol interaction analysis: FIG. 4 displays DSC
curves of PEG, cholesterol (CH), PEG:CH in a molar ratio of 1:10
PEG:CH (50 mg/ml and 25 mg/ml, respectively) and PEG:CH in a molar
ratio of 1:40 (12.5 mg/ml and 25 mg/ml, respectively). A shift in
the cholesterol melting point (from 147.degree. C. to 124.degree.
C. is observed as well as a change in the shape of the CH peak. The
melting point of CH didn't change upon increasing the ratio between
PEG:CH to 1:40, yet the heat capacity of PEG has been decreased
(from .about.47 to 35 cal/gr). ii) PEG: drug interaction analysis:
FIG. 5A displays DSC curves of PEG, Doxy-H, PEG:Doxy-H in a molar
ratio of 1:7.7 (30 and 15 mg/ml respectively), PEG:CH:Doxy-H in a
molar ratio of 1:10:7.7 (30, 15 and 15 mg/ml, respectively) and
PEG:CH:Doxy-H:DPPC in a molar ratio of 1:10:7.7:36 (30, 15, 15 and
90 mg/ml, respectively). A shift in the Doxy-H melting point (from
215.degree. C. to 210.degree. C.) is observed as well as a change
in the shape of the Doxy-H peak (FIG. 5B). iii) PEG:phospholipid
interaction analysis: FIG. 6A-B displays DSC curves of PEG, DPPC,
PEG:DPPC in a molar ratio of 1:32 (30 and 90 mg/ml, respectively),
and PEG:CH:DPPC 1:10:32 (30, 15 and 90 mg/ml, respectively).
Changes in the heat content of both PEG and DPPC are observed upon
interaction (from 47 to 99.03 cal/gr for PEG, from 6.6 to 5.1
cal/gr for DPPC). The addition of CH totally eliminates the
endothermic peaks of both DPPC and CH yet its addition does not
affect the heat content of PEG.
Example 8
Pre-Clinical Testing of Matrix Composition of the Present Invention
for Bone Recovery
Animal Models:
[0279] A. Tibial osteomyelitis in rabbit B. Bacteria:
staphylococcus aureus
[0280] All preclinical testing is performed in accordance with the
guidelines for Regulation of Animal Experiments in the State of
Israel and according to the Ethics Committee of the research
institution.
Test A): Determine the Relevant Bacterial Load for the Model:
[0281] 1. Cause a trauma to the bone (as determined in test A)--10
animals. 2. Fill the void (injured bone) by tricalcium phosphate
(TCP) material and seal it with Bone-Wax. 3. Load the site with
defined amount of bacteria by injecting it into the site. 4.
Duration--.about.22 days. Clinical signs and body weight (3.times.
weekly) is monitored. 5. At the end of the incubation time: bleed
the animal for basic Hematology & Biochemistry blood (prior to
the termination of the test). 6. X-Ray of the tibia prior to the
termination of the test (day .about.20) 7. terminate the
experiment, and harvest the tibia for bacteriological test. 8.
extract the bacteria from the bone and determine the bacterial
concentration (as described below)
[0282] Determination of bacterial concentration in the bone marrow:
The bone marrow and the intramedullary canal is swabbed with
sterile cotton tip applicators for gross culture analysis of
quality assurance. The inoculated applicator is streaked onto blood
plates and then placed into 5 mL of sterile TSB. The plates and
tubes are then incubated at 37.degree. C. for 24 h and growth is
recorded.
[0283] Determination of bacterial concentration in the per gram of
bone: The bone is placed into a sterile, 50 mL centrifuge tube and
weighed. The bone is then crushed and the final product weighed.
Normal sterile saline, 0.9%, is added in a 3:1 ratio (3 mL saline/g
of bone), and the suspensions are vortexed for 2 min. Six 10-fold
dilutions of each suspension are prepared with sterile, normal
saline, 0.9%. Samples (20 .mu.l) of each dilution, including the
initial suspension, are plated, in triplicate, onto blood agar
plates and incubated at 37.degree. C. for 24 h; colony forming
units are counted at the greatest dilution for each tibia sample.
The S. aureus concentration is calculated in CFU/g of bone.
Test A) Determine the Relevant Bacterial Load for the Model:
TABLE-US-00001 [0284] Addition No of of Bac- ani- Dura- Group
Trauma teria mals Treatment tion A Test Positive Yes (L) 3 TCP
(control) 22 days B Test Positive Yes (M) 3 TCP (control) 22 days C
Test Positive Yes (H) 3 TCP (control) 22 days D Con- Negative No 1
TCP (control) 22 days trol
Test B) Determine the Bactericidal Activity of the Matrix
Composition of the Invention:
[0285] 1. Cause a trauma to the bone (as described in test A)--13
animals 2. Fill the void (injured bone) by TCP material and seal it
with Bone-Wax. 3. Loading the site with defined amount of bacteria
by injecting it into the site (the load will be determine following
the result of test A). 4. Duration--.about.22 days. Clinical signs
and body weight (3.times. weekly) is monitored. 5. During the
incubation time: bleed the animals for basic Hematology &
Biochemistry blood panel at day 7 and 16 (prior to the termination
of the test). 6. X-Ray of the tibia at day 1 (or 2)+at day
.about.20 prior to the termination of the test. 7. Terminate the
experiment, and to harvest the tibia for bacteriological tests. 8.
Extracting the bacteria from the bone and determining the bacterial
concentration: as described above for test A. 9. Local drug
concentration is assayed.
Test B) Determine the Bactericidal Activity of the Matrix
Composition of the Invention (BonyPid):
TABLE-US-00002 [0286] Addition No of of Bac- ani- Dura- Group
Trauma teria mals Treatment tion A Test Positive Yes 6 BonyPid 22
days B Test Positive Yes 6 TCP (control) 22 days C Control Positive
no 1 TCP (control) 22 days
Test C) Toxicology of the Matrix Composition of the Invention:
[0287] 1. Cause a trauma to the bone (as described in test A)--24
animals 2. Fill the void (injured bone) by TCP material and seal it
with Bone-Wax. 3. Loading the site with defined amount of bacteria
by injecting it into the site (the load will be determine following
the result of test A). 4. Duration--.about.45 days. Clinical signs
and body weight (3.times. weekly) are monitored. Termination time
is determined according to the X-Ray results taken during the
incubation time. 5. During the incubation time: bleed the animals
for basic Hematology & Biochemistry blood panel at day 0, 10,
30 and 45 (prior to the termination of the test). 6. The animals
will be bleeding for blood-drug-concentration analysis at days 1,
3, 10, 16 and 30. 7. X-Ray of the tibia at day 2, 20, 30 and 43
prior to the termination of the test. 8. Terminate the experiment
and harvest the tibia for Histology tests. 9. Histology tests for
the injured site to 50% of the animals (12 animals). 10. Extracting
the bacteria from the bone and determining the bacterial
concentration for 50% of the animals (12 animals) as described
above.
Test C) Toxicology of the Matrix Composition of the Invention
(BonyPid):
TABLE-US-00003 [0288] Addition No of of Bac- ani- Dura- Group
Trauma teria mals Treatment tion A Test Positive Yes 6 BonyPid 45
days C Test Positive Yes 6 BonyPid 45 days D Control Positive no 6
BonyPid 45 days F Control Positive no 6 BonyPid 45 days
[0289] The foregoing description of the specific embodiments will
so fully reveal the general nature of the invention that others
can, by applying current knowledge, readily modify and/or adapt for
various applications such specific embodiments without undue
experimentation and without departing from the generic concept,
and, therefore, such adaptations and modifications should and are
intended to be comprehended within the meaning and range of
equivalents of the disclosed embodiments. It is to be understood
that the phraseology or terminology employed herein is for the
purpose of description and not of limitation. The means, materials,
and steps for carrying out various disclosed functions may take a
variety of alternative forms without departing from the
invention.
* * * * *